I agree starting with a later model larger flatty would be best and I'm looking for victims, trust me. I've just located an engine with potential and I'm currently gathering information about it, if it pans out I'll buy it. I really want to stay with a flathead, but that desire has to balanced against budget. A V8 is not a realistic option at this point of the project. If the other engine doesn't work out I can go to plan "B". Plan "B" is based on research I've done on this site and others, if my 218 block is good I can bore it out and use the crank, rods and pistons from my 1950 giving me 237 cubic incher. While it's not a 251/265 it is a better starting point than the standard 218.