So I dragged a 40 horse long block that I've been tripping over to BAP, but no one was interested. When I was putting it back in its spot, I thought, why don't I clean it up and put it back together to have as a small runner in case I come across something that needs and engine!

So I have a long block, I have 3 extra heads, I have an intake. I have an oil cooler that could probably be cleaned out. What kind of things should I be looking for that are significantly different from a 1500? Are the cylinder tins different? Fuel pump? I think the exhaust is different (different width). Can I put a 12v flywheel on it? Are the rockers different? What about the push rods?

Any other tricks I need to watch out for? I have a gasket kit coming with new push rod tubs.

Yeah, I've noticed the narrowness. The intakes come in at right angles and the ports are flat vs the regular single ports, which come in at a slight angle. I've also noticed that the exhausts are more narrow too. I am pretty certain I have the right doghouse but I'm still curious about head tin etc.

Looks like the fuel pump is the same. I can put a later generator and stand on it. Rockers I haven't researched yet.

Right. most of the tin is different, esp. the front and back pieces that have to line up with the exhaust ports, which are closer left-to-right than the bigger engines. The fuel pump would be the same. Intake manifold, of course, is shorter left-to-right. I think rocker arms are different. I know the pushrods and tubes are shorter. I think the later flywheel fits.