Hi Brett,
FWIW:
1. One major concern appears to be not to damage the Model A steel wheel paint; hence, if one finds a local, very trustworthy person in any tire changing establishment who really "cares" about "not" marring wheels, that option with that person could be most wise; however, if any such establishment has the normal uncivilized gorillas changing tires, then "always" do it yourself -- it's that simple!
2. For DIY, per reply #9, one can make a similar, simple square wood frame. I made a lighter one with (4) 1x4's on edge, braced with (4) 1x4's laid flat at 45 degree angles on top for placing one's tire on top of same with the hub cap pointing downwards so no metal touches ground or concrete. Full length 45 degree 1x4 corner braces terminate in the center of each 1x4 on edge & are supported with a vertical 2x4 below about 7" long, attached to the in-side center of the vertical 1x4.
3. For difficult bead breaking, I made an attached & removable wood bead breaker with a rotating 2x4 horizontal lever fixed to (2) vertical 2x4's with a single through-bolt, -- examples & further details are shown on line if one searches something like "wood tire bead breakers", then use one's imagination to complete same. Works great.
4. Once the bead is broken on the in-side, the out-side bead is easy to break.
5. Plastic bags work great -- just installed (5) new tubes in my (5) tires in a jiffy -- used no talcum powder, no voodoo dust, & no hog fat -- changed tires on my Model A's for over 50 years.
6. After doing one (1) successfully, the next 1,000 are quite simple.
7. Each to his own how to do it; just hope one day this may help somebody to remove stubborn Model A tires.