I went through the same process. I cracked the head on my '89 2.6, started blowing out head gaskets, and finally bought an AMC replacement head from those same people. The original head was a number 4 casting, but there were too many problems. It had cracks, the valves were burned. Take a look at the pictures in the link below.

I highly recommend the AMC head from these people. My dealings with them were good and very easy.

AMC Heads at Aluminum Head Rebuilders

The AMC heads are new, not rebuilt.

1989 Trooper, 2.6
1989 Trooper, 2.8
1992 Ford F-350, 7.3

My Photos