Maybe I didn't search enough, 1hr & no matches, but here is what I've got and all I could figure out. can you provide more info on these numbers?
Block cast #
3837004 GM25
Block Ser. #
Fb05H
(Fint June ?? Truck)
Head cast #
3835913
GM10
('54 235)
These might be mismatch parts, they're out of a '55 3/4ton truck with 4sp trans.
Thanks