Springfield 1911 Questions

Okay, stupid question time. I accidently bought a Springfield 1911A1 Stainless I .45 ACP on an auction site. I have an older Springfield MilSpec, late 90's vintage.

My question is do all of the commercial Springfield frames have NM serial numbers, and are they matched to the slide? The last 3 of the serial number are electric pencil engraved inside the slide.

It was listed as non functional but after cleaning the only problem I found is the trigger pull feels light, I haven't put a scale on it yet. Before cleaning the slide went home in slow motion, but everything else felt good.

They do not all have NM and the slide is not custom fit to the frame. Anticipating your next question you can switch uppers between the two frames. Some would say that is the best of both worlds. 

Len

Generally accepted that NM marked frames were assembled in the US. N marked were assembled in Brasil.  Today i believe all are made.and assembled here.

Thanks for the replies. Bought it on egunner for $395. $444 after shipping and FFL, less than the last 1911 I bought. After cleaning the slide wiggles a touch, but the bushing is tighter than my MilSpec. I need to tweak the trigger spring a bit. All in all a good find I think.