if they are the fast burn heads (they will have what looks like mountain peaks on the front surface) and you have a manifold that will match i say go for it they make some decent power especially with the right cam.
they can be had from
http://www.jegs.com/p/GM-Performance...49896/10002/-1
the intake manifold is different but everything else will fit up (except the tbi unit(however a 454 tbi should fit fine))