I picked up a replacement engine for my 216, it was in a 56 GMC 1/2 ton truck the seller didn't know if it was original or was replaced at some time. Block casting # 3836340 Light Blue color. Serial # on the lower block # W 23 206 and close to the distributor # 34784 Head casting # 3836848 Looking through the info online and on here it looks like it's a 261 with a higher compression head. What I would like to know is if my research is correct. Thanks for any information anyone can provide.
