I bought a barn find estate sale 70 convertible that hasn't been driven in 6+ years.
The air appears to be still original and all there, the compressor spins freely. I took the belt off until i diagnose it

Is there a checklist of parts I'll need to convert it to 134, and the process?
​​​​​​ Is this something a diy can do? Or do i need to find a professional?

Thanks in advance

 

The compressor CLUTCH may spin freely. You have no idea if the compressor spins or not. Leaving the belt on and spinning the clutch has no detrimental effects. That's what it's designed to do.