1970 AC question

[frenchy51]

I'm getting ready to paint and reupholster my 1970 Burb. It has a fairly decent roof (ceiling?) mount full length AC unit that doesn't work at the moment, but I think it's repairable and usable. I have a couple questions: Should I go to the trouble of restoring it or just go with a Vintage Aire type under dash unit with front vents? What have you guys done? Will the front only vents cool that big cabin? Will a restored original roof unit cool better? Also-anyone know how to get the darn thing off the ceiling? I can't see any obvious attaching hardware?? As always-Thanks in advance