10-4... when I get the truck back I'll post some more numbers.
The block number crosses to a 235... 3769716
I don't have the cylinder head number yet, but I'll get all that.
Thanks for the comments.
And you're right, lots of stuff can happen in 57 years. My truck may well have come out with the 261 and who knows (?) it could have blown and someone had the 235 on hand and dropped it in.
Dan