Now the top is nice. Just in case we get the car running.
Replacing a convertible top is not overly complicated, but it isn't easy either. It takes a professional 7-8 hours to correctly install and align a top, and that isn't taking into consideration the possible need for the restoration or maintenance of the top frame.
But we think you can do this yourself armed with a few tips, the right tools, and a good set of instructions. You should be able to install a top at home with a couple of buddies in a weekend. To get the insider tricks, we took our project '71 Buick GS convertible to Gary Lette of Redline Auto Sports in Wilson, Oklahoma, so he could give us a hand and make sure it looked good.
This top has certainly seen better days; it's hard to believe it is only seven years old. | 
The teardown started with removing the weatherstripping. This stuff was leaking pretty badly, so new pieces from SoffSeal were ordered. |
The staples in the top were gently pried out. Here, the top staples in the upper curtain bow are carefully removed. The rear curtain was still in good shape, so we were trying to save it. In the end it tore and was replaced. | |
Any top project should begin with an assessment of what parts are needed. Some cars originally came with a vinyl rear window (in upholstery-shop lingo, rear curtain), some came with glass, and some glass-windowed cars often received vinyl replacements after the glass broke. Glass is better but more fragile. Plastic has a tendency to yellow over time. If you are buying your parts from a restoration house such as Year One, ask the staff to recommend the correct style and material. We ended up using the glass replacement back window that came with the top for '68-'72 GM A-bodies. If your A-body is a '64-'67 model, the glass is zipped in; for '68-'72 it is sewn in. In addition to our replacement top, we also picked up a top-pad kit that protects the top from being pinched in the folding mechanism.
Virtually every convertible top is installed in the same fashion. The top is stapled to the frame via tack strips. Depending on the age of the vehicle, the tack strip will be either pressed cardboard ('60s and '70s vehicles) or vinyl rubber (modern convertibles). The replacement solution is vinyl rubber-better because cardboard holds water and the top frame is metal. Owing to this, the rear bow on our '71 Buick GS had several sections of heavy rust. While our piece was savable, it was very close to needing replacement. The old cardboard is very difficult to remove and can take hours, so be prepared.
GM A-body cars use a floating rear bow, so the position was marked using some green tape and a Sharpie. This ensured the bow would be put in the same position. Don't worry if you lose it; most upholstery shops have all the measurements in their guidebooks. | 
There are two bolts holding the rear bow in place. With those removed, the bow was pulled out. We needed to replace the well liner, which is stapled to the bow underneath the rear curtain-the canvas was torn during the removal process. Luckily, we had a new curtain on hand just in case. |
The original cardboard tack strips were in really bad shape. They do not come out easily, so a flat-blade screwdriver and a mallet are helpful here. We replaced the old stuff with new, vinyl rubber tack strip. The tack strip was pressed into the bow and screws placed every 8 inches from the back side. | |
The well liner and water trough sustain a lot of abuse over the years, especially on a leaky top. The water trough is made of thin plastic, and the small tabs are easily broken. Most classic convertibles are missing the troughs altogether. After-market versions are usually made of fiberglass with tough metal mounting tabs. The well liner is your trunk's last line of defense against moisture. This piece of vinyl separates the trunk from the interior of the vehicle, often retaining water for days after a storm. Subjected to water and the sun's harsh UV rays, the material eventually breaks down. Replacing this liner usually requires removing the rear window at the lower bow.
If your top is power-operated, the cylinders and pump could probably use some service. If there is a film of hydraulic fluid under the rear seat, then you likely have a leaky cylinder. An O-ring will sometimes fix the problem, as older cylinders were sealed with a simple felt disc. One of our cylinders had a bent rod, so replacement was the only option. At $125 each they are not cheap, but the ability to hit a switch is nice. The pumps are rebuildable in most cases. Kits should be available for most pumps at your local hydraulic supply or electrical motor rebuild shop.
The original cardboard tack strips hold water, which leads to rust. The rear bow had some serious rust issues. It was sandblasted and painted with Eastwood's Rust Encapsulator. If the rust had been any worse, this bow would not have been usable. | 
With the rear bow out, the water trough was removed. The original plastic trough was in bad shape, so we replaced it with this slick fiberglass piece from Year One. This one has metal mounts, which won't tear out like the original plastic. Don't just leave this piece out-your trunk will end up full of water. |
The top pads were opened up and stapled to the top strips. Here, Gary Lette from Redline Auto Sports sprays adhesive to the vinyl, the foam pad, and the cloth. After the adhesive set for about a minute, the foam was placed over the vinyl, then black cloth wrapped over it, and the factory screws put in to finish the pad installation. | |
The weatherstripping has to come off to complete the installation of the top, so you might as well replace it. The key here is to use a quality kit like the one we chose from SoffSeal. Unlike cheap kits that don't have pre-drilled holes and OE-type materials, the complete kit from SoffSeal fits as well as or better than the original and should last as long as the new top.
The major tools needed to complete the installation are an air compressor, a good-quality staple gun, and we suggest professional-quality glue from any upholstery supply shop, sprayed from an inexpensive primer gun with a large fluid tip.