Clutch replacement on street?

[WorkinLonghorn]

I need to put a different clutch in my '69. I called around my area (L.A.) and one old timer told me that if I brought in the parts, he'd install them for $800 (!!!). I know overhead has gone crazy around here lately but I remember in the '80s I just crawled under my '63 (with a 230 ci. 6 and 3 on the column) slid the trans. back a little and slipped a new disk in there in about 45 minutes.
How difficult would it be to swap out the clutch on an iron case 4 spd. Is this something that an old geezer can do on the street with a floor jack? Or would I need to fab a trans. holder for the jack and even then is it practical... -BA