chevy engine identification

[Hunter5796]

Hey guys, I'm new to this so I guess I'll just post my question. I purchased a SB Chevy engine a few months back, running engine minus carb,it had a set of camel back heads on it that supposedly were original to that engine. The # on the back by bell housing reads 2970010. Below that on the actual back of the block,hidden by fly wheel it has the numbers 0.10 & right below those are the #'s 0.20. I've been told those stand for an additional 1% Tin and 2% Nickel to strengthen the block. Can anyone shine some light on this subject and maybe have an idea what this originally came in. Oh...the # on the front of the block by pass side head is V0210TBX. I'm lost, thanks.

[Henry Rifle]

You sure it isn't 3970010?

[robot]

TBX suffix means EITHER a 1970 truck 255hp 350 with a turbo 350 tranny and 1x4bbl carb installed in a 10, 20, 30, or G series body OR it is a 1979 Calif emissions 350, 155hp with a turbo 350 tranny and 1x4bbl carb installed in a CK 10 or 20 body with a VIN code "L"