Hi Andy, I can't be 100% sure that my assumptions are correct at all, its all based on google imagines I have seen so far.
The dash instruments are not the same as any '37 car Dodge, they seem to be same as a truck, as I said the engine number starts with T38...., not D.. It is a MC model on the registration which I believe is the truck chassis code for that yet, the petrol/gas tank is under the front seat. I have no idea about the windscreen frame, I haven't seen one the same on google as yet. A convertible sedan seems to be very hard to find many pics of, I haven't been able see one on a truck chassis.
I haven't received the car yet, next week when I do, I will look for a plate or stamping, but the bloke who I purchased it from, did the restore and he doesn't know the body builder.
Yes, I have been keeping an eye on it for some time too. Its been a Maryborough QLD car from day one, so a little sad to take it down to Brisbane, 3 hours away.