The Windshield is from a later CJ5 or so, judging from the amount of rake it has. The mirrors probably came from the same donor from the looks of them. The original windshield would have been a two piece glass design, with a rubber seal between the two panes.
As far as the serial number, the engine is at least correct for the model designation of the prefix MD. All M38A1s were MD Willys model MD, while the M38 was an MC, and the WWII Jeep was a MB.
Here's a closer look at the tub. planning to replace floor pans, tank well, and maybe bed floor. Outer body parts are ok with a few whiskey dents with bondo, but not too bad.
Bondo monster got a loose on the tailgate area.....1/4" in a couple places. Seems they were attempting to smooth it out for a camo vinyl wrap that was covering the body at one time.
The tub doesn't look too bad at all. The Jeep pictured above was a lot worst wear when it was brought in. The pictures bellow were from the starting point.
We were passing this around last week in PM messages. I found these in the old International Harvester complex here in Ft. Wayne. Your tub isn't in all that bad shape. Just get a good spot weld cutter. Ira once said; "If I say I'm going to cut out another brace, just take me out and shoot me". We believe welders got paid piece work for each spot weld.