The only interchange problem we ran into with the Ramjet was fitting a short water pump in place on the long-style pump supplied with the crate engine. One bolt on the plastic timing chain cover sits up far enough to interfere with the short-style pump. We had to seriously grind the head of the bolt down and make a minor clearance in the pump itself to get it to fit (arrow). We can still get a wrench on the abbreviated head, but barely. This applies to any GM small-block using this type of cover, but is not an issue with long-style pumps.