The front is 1940 but the brow trim over the grill is missing. It looks like the side and hood trim was removed. The opening in the rear fender is a custom touch. Shaving, decking, and nosing were common back in the day as well as chopping the windshield frame to get a lower appearance. Carson tops were the cat's meow back in the day. The car may have later model frame or drive train but there are no photos so a person can't tell that for sure. If it was done long enough ago, it may still have some original equipment under there. Top irons can be cut down to match the windshield cut but it is certainly a lot of work and it requires the whole top to be modified. The Carson type top mod would have been easier and acceptable back then. The side windows should still have the brite metal frames around them if they are still in place. The dividers between the front and rear side windows would've also had to be modified.
It's a custom so anything done on it will require custom fabrication to get an acceptable look to it. I've seen much worse examples out there. The potential is there to make a nice car out of it but It would be way too much work to restore to original at this point unless someone was sentimental about it.