The 2.8 can easily be swapped for a Camaro 3.4 which all around was more durable. Edelbrock makes a smog legal manifold last I checked for the Chevy S10.
I even think you can stroke the 3.4 to almost 3.9 with pistons from another engine, and a later crankshaft. That assumes you want to stay with the stock set up for some reason.
Other then that a EROD swaps in easy enough, and I would go that route before a 4.0 swap.