I wish we had a way to accurately know how many of the second generation convertibles are left. I know the museum in Irvine had one which is presumably in a warehouse in Texas now.
Especially challenging to implement in a country where the prevailing political ideology equates a lack of means to a moral failing and wealth to intelligence.
On the other side of the deal, Daihatsu got to sell DeTomaso editions of the Charade domestically since Alejandro DeTomaso owned Innocenti at that point youtu.be/9kAzdtMOpHM?...
Older bikes often had horizontal/semi horizontal dropouts and if the wheel wasn’t tight enough, pedaling torque could cause it to rub on the non drive side chainstay.
If you remove the wheel and try spinning the freewheel, like if you were coasting, see if it spins easily or feels draggy. If it feels ok, try spinning the axle and see if that spins easily. That will at least help you pinpoint the cause, assuming nothing else is rubbing the wheel/tire.
What happens when you spin the wheel? If it’s just a cooked freewheel it’s an easy fix, and if it’s the hub internals it still could be but probably easiest to just replace the wheel at that point.