engine parts swap

I have recently bought a 1991 chevy s10 with the 4.3 v6, standard. This truck is somewhat tired sitting around 274,000km. I was wondering if it is possibly to swap parts from my older chevy 4.3 to a newer 4.3 vortec, specifically out of my friends 1998 blazer 4x4. Any help would be appriciated.