Considering Buying 1992 GMC Jimmy

I am looking at a 1992 GMC Jimmy 4.3L HO 120k. The truck is in excellent condition interior and exterior. I test drove it last night and it was a little rough the guy said it may need to be tuned up (last tuned up about 2 years ago). I think it just needs to be run since he only drives it about 1 time a week. He is asking 2000 for it. The only other thing that concerns me are the power windows go up and down really slow. I am thinking the motors are just about dead. How hard are the motors on these things to replace? I am considering offering the guy 1500 for it and see what he says. Any advice on what else to look for?
Also, the backup lights don't work. I am hoping it is just the bulbs but anybody else have problems with those?

Thanks,

Tim

Watch it, sounds like the Injector is gone in it and is a $300-$500 job depending if you want to do it yourself or not.

It is TPI not CPI so I don't think it is the injector.

Oh,

Does it have the air filter on top of the engine or the black and orange vortec name plate?

It has the vortec name plate.

Than it is a CPI and my previous advice stands as being true.

It has 6 seperate injectors. I thought CPI had one injector?

A 1992 Vin W Vortec has one pressure regulator and one injector which batch fires 6 poppets valve at the end of each fuel line.

Here, I own the engine, look at what I am talking about.:

http://www.s10forum.com/forum/showthread.php?t=113559&highlight=cpi+replacement