My 37 has a different "hoop" for the driveshaft which would be like what you are trying to do. I think if you supported it correctly, it would work fine. You may also want to look at the steering....it seems the wheel is on the wrong side
I knew I had a pic. Just make the "hoop" smaller and make sure you have clearance for the driveshaft....
I really like what you have done with your frame horns. What are the plans for your car? I personally hate the way the stock horns look, I think they're too wide, but I doubt I'll do anything about it.
I put an HT beam under a 39 Plymouth chassis with just a couple of notches each side and hacking the top off Holden beam, the stock one is much stouter. The VK Commodore rack I used was fine for width, yours looks like the pinion is under the motor I was just looking at the 'hump' and don't know why you'd want to get rid of it either, it's under the seat and provides depth for the battery box (mine's swapped to the right) and clearance for the muffler I think the worst thing about the US and Australian floors is that they're too low at your heals, the Canadian Plymouths and other corp cars all have an intermediate ramped section there... You're still going to need a trans hump.
Have you guys who've lost or considering losing your bumper irons and mounts considered how you're going to support all that sheet metal from flopping around on the radiator mount?
Looking at these pics of a 39 makes me want to get another,I had a rare 39 sedan delivery that I had to sell since the city was on me for too many vehicles. I sold off all the extra 39 parts but kept the six speed parts so I am looking for another.