Unless alternative clean fuel are introduced, chances are high we'll have not much option than go that way. We're already at $10 a gallon here.
As said in vid, you'll need much more than an eCrate motor. Not even talking about the inverters, controllers, cooling, batt packs etc...
In a 73, even using a single motor on the rear, you'd need different axles, suspension, brakes, modify the floors. Lots can be done, but it will be much more than the $4000 that the engine alone costs. Seen a few vids on the companies offering the conversions and they all talk 80-120k. They of course calculate their labor, fab time, costs and want make a buck in the process. For say 1/3 of that price you could may be better be off by buying a used/crashed but functional EV and somehow mix it with the 73 vert. Which we agree, would be much more sexy than the ugly things they want us to drive these days.
But even that isn't that straight. I've red a few times that Tesla to name just one manufacturer, cancels or modifies functionality via the software if car is found by the computer to not be a legit Tesla or not be serviced by their official service stations. You need some serious tech knowledge to go around that alone and program your own controllers/interface.
It's too soon for now, but it's likely the aftermarket will grow quickly for EV parts/solutions. I mean look at Holley for instance, they are a "fuel" company, their very existence is a stake, they are one of the many companies that will have no choice but invest in other tech or die.