2.9L Heads

[1987 Ranger]

I tried the "search" function but didn't find an answer. I understand 86-88s have junk heads and 89-92s have revised, better heads. My question is can 89-92 heads be used on a 86-88 motor? Is it a straight swap, or is there any difference that prohibits the swap?

 

[gaz]

The bolt on like their getting paid.