NP205 in 76? K20 - what do I need?

[crosby]

I am trying to put a NP205 in my mid 70s 3/4 ton 4x4. It has an 87 body and bed, but the frame is rotted in front of the rear spring mounts. So I bought another frame, and plan on putting the drivetrain in before I pull the body over. I have the original? Th400 and NP203 in it (full time ) and want to put a NP205 I picked up for it when I got the frame. I have discovered the transfer case adapter I need is expensive, and don't know what else I need. Isn't there a coupler in there too? I am not concerned about driveshafts or speedo cables yet, but what do I need to make the 205 work? Thanks very much for any help you guys can provide.