I agree, heck all that would need to be made to make a '39 Standard is the front fenders, hood, dash, and of course a banjo steering wheel. The '40 Ford coupe, and sedan are among the oldest, most popular kits that are currently offered. The sedans are more expensive, but are still readily available. It just seem like a likely trans-kit to me.
And while they are at it, make 1/25th scale '40 pickup cab, and bed, so one could build an entire line in the same scale.
As you can probably tell, I've built a ton of these kits. And, have modified them in every way I can imagine.
Olderndirt