I've got a 2000 PU w/ 8ft box and finally looking to replace the dented mess back there. Wondering about compatibility of boxes outside of the 2nd gen group (98-01).

 

I think there would be a good bit of fab work required to make it bolt up, and then you may run into problems with the electrics if you got a newer bed...... There are sources for rust free parts, just do a google search.