[AtomicYJ]

'57 3000 and 4000 series trucks had 265 V8s that use the same block casting numbers as 283s. The stamp code on the light truck engines in L, LA, or M (possibly 4000 series) that will denote it's a 3000 series 265.

It took me a hot minute but i found a 265 for my '57 3200 that came out of another '57 3200. Rebuilding the 265 will cost more than a 350, but I think its worth it.