You didn't miss it Maxvamp, I did. It is a 250 C.I.D. GM out of a PU truck. I ran the numbers down on it and I am sure of what it is. Sorry about the omission. Getting old I guess. I proof read the message, too!
Ted65Mali, you are right on the money. I drug the heads out in the sunlight and cleaned the numbers with carb. cleaner for good measure. Yes, I know I am supposed to wear the d--- things but they aggravate the snot out of me and I did not have them along on the first time I looked at the numbers. I was able to read the numbers out in the open without the glasses, but I used them to be sure. I thought that in 1975 GM went to integral heads on all inline sixes. Incorrect? Anyway, it looks as though one will be as good a candidate as another as long as it crack checks o.k.
Moral: Pay attention when proof reading and wear glasses. Thanks guys, I really appreciate the help. I obviously need it!