Yes, I think the engine is a 56...but maybe it's a '55 now that I look at the numbers.
Here's what I see.
B54848
GM25
3836848
My truck has a foot starter and a 6 volt battery. I'm obviously not savvy on these things so I do appreciate the help. When I bought the truck I was told the engine had "no power" and may have overheated at some point. I got it running and it is very weak. I have an opportunity to pick up this '58 engine that's a solid runner, so I thought I'd just do a swap and then take my time to rebuild the old engine somewhere down the road.