HEad swap

HEre is a good question. I have an 89 XJ larado w 4.0 ltr. Runs well, alittle piston slap on cylinder one, but plenty of oil pressure and power. I have a 99 4.0 ho from a freind, I was wondering if I could swap the heads out, would it bolt to the 89 block? I have all the intake and exhaust manifolds.