Who knows ?
It is definitely not a Vin code K block.
It is a 4 inch bore and correct stroke.
My truck is a 1500 series GMT400 so not a one ton.
My brother law owned it before me he claimed that the dealer put a new engine in at 90K.
It had the stickers on the valve covers Goodwrench but I do not think that it was.
Looks like it was a pull from a 87 caprice.
The roller bosses were in all the blocks except a few Marine from 87 on.
I have only seen one from a TPI block that was non-roller.

Mains and cam bearings worn out but it never knocked crank Mics fine the bores are ridged about .010. Ridge reaming and dingle balling it tonight.
I'll mic the pistons may have to knurled them.
It will be fine.

I am disappointed because I was considering a turbo for later.