I've tried the usual engine and block casting # sites and even checked with a Mitchell Manual but have been unsuccessful identifying a rebuilt 250 I picked up at an auction this weekend. Can someone help me identify what year and model Chevy it came out of base on the following: engine # F0 309TA and block casting #3677178? How hard a swap would it be for my 1952 2-ton dump truck with a 4-speed tranny with the 235 currently in there? Got the 250 for $70, just had to bring it home and then figure it out!