Been in the works for a few years now on wanting to build one well today is the day to start. The XM177E2 was the first rifle I was issued when I was in 2/75th Rangers in the early 90's. Actually still have my arms room card when I was a pvt LOL. So basically just bought a complete Colt assy minus lower and moderator. I dont remember what mine looked like exactly as it was 25 or so yrs ago.
Using retroblackrifle as a reference for parts and pics. Want to make sure its period correct as much as I can I'll list parts below that I know of.

Upper
Colt A1 style upper w/brass delfector ( I think the E2 didnt have one?) can anyone confirm this if some had them.
11.5" barrel c mp cb barrel (he says 1-7 but will double check that for me)  shaved bayo lug.
6 hole handguard with single heat shield
Fat round forward assist
new style port door ( need to find a period correct one)
Colt CH
Colt BCG

Lower
4 position tube ( Going to pick up a brownells 2 pos tube)
Colt N1 stock (eventually going to buy an aluminum acetate - who has retros?
Colt LPK (dont know anything about it yet) normal a2 grip (what grip is period correct?)

Picked all that up for $625

Going to pick up an 80% lower and send it to Braceman to have all the engraving done (complete colt w/my old S/N). Who would be the best for anodizing? Should I get the upper done same time and what other parts need to be the same color?
Anyone see anything else that needs to be looked at/changed? Thanks

Rifle supply has the early port doors. Essentail Arms has the nicest aluminum stocks, in my opinion. Hit up "Brick" on gunbroker for your moderator. A lot of us just shoot Norrells moly resin, grey-black flat. Grey ano is hard to find someone to do, most won't do small batches anymore. Also, check out John Thomas, at Retro Arms Works, for anything you need gunsmith wise. He does amazing work.  Also, you may want to cover your SS# on your card, you never know.

Looks like you're well on your way! Enjoy the build process, it can be fun.
Scott

Dude your SS#! Hello!

Thanks you two LOL  Didnt even think to cover that area up.

I'm glad you bought that. I had emailed the seller. I was hoping it didn't have the brass deflector, but even so was seriously making him an offer on it.

Yeah I had emailed him last night for better pics and told him this am I would take it. Glad I did. Now looking for correct parts to complete this but this gets me in the ballpark. Some stuff I'll leave until I find the correct stuff.

For using the Norrells Moly resin would it be better on an un-anodized lower or anodized? thanks

Tear drop FA? and no brass deflector. Keep the upper and you’ll be on the way to another build.

Where did you find a colt 1-7? Holy cow the only one ive even seen was 800.

I'll second Brick for a moderator, but it'll be too short with this barrel unless OP SBR's it.

There's other moderators out there that would make it legal length. Ive already got an sbr lower don't know if I want to do another one for a little less than an inch!

Would it be bad juju to take this colt upper receiver and mill off the brass deflector? Or just go to brownells and get the nds? Going to use the moly resin all both lower and upper anyways.
Also what all parts need to be the gray color? Thanks

Brick makes an extended version, as well as the normal length version. John Thomas can pin and weld, and repark the barrel and moderator.  As far as Molyresin, I've used it on both anodized and lowers in the white. I haven't seen any difference in coverage, color, or anything else, for that matter. I did scuff the lowers in the white before application. Just clean and degrease everything well before application.

There are some guys who can mill it off, but for $150, I'd leave it as is, and get a Brownells upper when they're back in stock. As far was what's gray, everything but the handguards, grip, and stock. You can get A1 grips from Sarco for a few dollars, to swap out the A2 grip you have.

I can mill it off I do machining at work. I'll wait a bit but I'd rather have colt parts so I might just mill it anyways.

The Retro Way is to use that to make a C7 carbine or rifle so I vote for "Build it not mill it!"

That upper is pretty desirable to some people, buy a real on that anodized the correct color, don't mill that one.

I hear ya'.

Really? I had no idea. Now i'm already thinking about another project...

Who can tell if this is 100% colt? Also what would be a good price if it is?
Thanks