ArticCat - it is my understanding that they did not change the basic design too much for a good while... but I can't say for sure. Maybe the '47 2nd series -'55 1st series guys will weigh in here.
Rance - some people have used the mechanism like the one in a chevy s-10 or the full size chevy truck from the 90's - I actually bought the wire spool type holder off a '96 chevy myself from a junkyard to try to mount it up on my '65 - but then I found out RJ had an original type one for sale, so I figured I'd try it out first. People have used all kinds of things to hold the tire up.
I once thought about using a few long J-hooks with bolt ends on them, mountin' them somewhere, then sticking the bolt ends of the J-hook through the bolt holes on the spare... then twisting on a wingnut to secure it. I figured this would be a pain though trying to line up two holes, under the bed....
-W