Down to frame but don't think I have what I thought I had

I'm certain my scenario isn't new. I purchased a CJ2A restoration project. Previous owner had admittedly replaced the engine with a F-134 from a '53 CJ3B...I have the box on the hood to attest to that. This is a father-son project and we're down to the frame (well, almost) and getting ready to order new parts where they're needed so we can start our way back up. The problem is I don't think we have a 2A frame. I think it's a 3A frame, which may explain the fact that we have a Dana 44 in the rear vs a 41.
We need help before we hit the "order" button on a bunch of parts. I wasn't sure whether to go to a 2A, 3A, or 3B forum so I figured I'd start here at KW.
I've attached a photo of what it looked like before we started. Passenger side mount of the spare I think is also an indication of 3A. The second photo is where we stand now.
My two questions:
1) Can anyone confirm whether this is a 3A, 2A, or some other combination frame? I have no plate
2) If it is a 3A frame, can a 3B body be mounted? The body is made up of paint, bondo and some sheet metal so I don't think it'll survive media blast. Since I have a 3B engine, the higher hood clearance would be awesome.

I'm sure there are other obvious things I'm missing right now so I am open to any and all advice. It's a first restoration project so it's learn as we go.

The frame is neither a 2A or a 3A or even a 3B. What you have is an M38A1 chassis. The dead give aways are the front tie down mounts above the front bumper, the battery box mount is actually the 24 volt voltage regulator mount underneath of the welded angle iron box, then the final thing I see is the cut off machine gun mount on the cross member. I can supply a picture of the frame I had a few years back for your reference, but it will be Monday before I will be back.

As far as the body goes, if you want to utilize the F134, then you could go with a CJ3B body. It all depends if you want to keep with the flat fender look, or if you would consider the military pedigree, and find/purchase an M38A1 body. Anything you choose will be alright with most of us.

Another thing that popped to mind, the military engine serial number will start with M. The serial number is on the flat surface of the block deck, directly behind the water pump, before the head. This is unless the block has been decked somewhere through history, and the number was shaved off. This may help your decision.

Thank you. I had a similar question posted on the CJ2a page (since I thought this was a 2A rebuild) and got the same response. We definitely want a flatfender. If it's a new body in the mix, a 3B would be preferred (my son and I both like the look of the higher hood). Any thoughts on what hurdles to expect if we pursue that? I guess anything other than a true M38A1 body will require some creative installation.

By the way, the PO said the engine had been replaced with the rebuild F134. He put in the existing one to get more hp. Its another reason the 3B would be preferred, to avoid the air horn challenges with the lower hood.

There will not be too much trouble to install a 3B body on the frame. There is only slight deviations between the frames. Since you already have a 3A body installed, you can note any mounting differences. The grill mount will be the biggest hurdle, because the civilian model had a lower mount that requires a bolt. The second photo is of a M38A1 being placed an a CJ2A frame for safe keeping while the M38A1 frame was used to mock up the body of another A1.