Well, you are half right. The balance shaft is driven off of a gear on the cam. The balance shaft came into play with the first of the L35 RPO code engines (CPI) in 1992. The TBI motor did not come with a balance shaft and was in production until '94.

All timing sets used are chain driven.

This is a good read through on the early history of the 262:
Rebuilding the Chevy 262 by Doug Anderson courtesy of EngineBuilderMag.com

 

I think the Vortecs came around in 1992 so you probably have a TBI. I had a 91 Ext cab truck and ha the TBI 4.3 in it. I would have much preferred a Vortec engine if one was available at the time. As far as the fuel injectors it also might depend on how long it's been sitting around. You can actually buy a kit for the TBI unit kinda like a carb kit. Whatever you do, I suggest you buy a manual. Personal preference is factory, second is Chilton and if I need to have something to start a fire with a Haynes. The TBI units really are a piece of cake to take apart and put back together if running some chemical through it doesn't work. I noticed from your original picture that it's in a field. If it's been there a while you might have some "visitors" that have taken up squatter's rights - wasps and other kinds of insects like to make a nest in nice quiet places like fuel vents, air intakes, etc.
The timing chain isn't that hard to change. That engine is just a small block Chevy V-8 with two cylinders whacked off. You do have to drop the pan down to get the timing cover off. Don't get chincy on the chain and gears. Get some good ones and they'll last a long time.

 

thanks for all the input fellas.. the trade will commence this weekend.. i'll have more pics up then..