4.3 went on my Silverado, and I'm replacing with another 4.3 from a 95 S-10, any compatability problems? Everything I've read here says the 4.3 is a strong engine, but at 100,000 miles of problem free driving mine just up and quit, what gives?

Is it like the 1500 GMC pickup? That trucks a little too big for a 4.3. Better get a 327 to put in there.

Here's a link to the right forum for your truck
http://www.automotiveforums.com/vbulletin/f1090/

Although since it looks like your truck came factory with a 4.3L you might be better off here.

Personally I would do like Ducaire sayes, and dump in a v8.
It'll last longer, and might even get you better mileage.

It'll be an easier job than droping 1 into a S-10 since your truck should already have all the motor mount locations for the v8