All I have to do now is zero it.
I have the AR I want, with the options I also want if I want to revert back.
I mentioned before that I want to lighten it up, so the nice quad rail was replaced by a Magpul. So what if I don't like the Magpul? Well I wanted the quad rail in case my preferences change in the future.
I would be remiss not mentioning the original manufacturer of my upper. Yankee Hill Machine Co.
Here is most of what you need to start.
I needed a few more items. Like small screw drivers for the rail covers. A 3/4 wrench for the flash hider.
And here it is in my vise. That universal patternmakers vise is handy for this application. I need that yellow handle plier like thing for the circlip. Or snap ring. Whatever. It's a pain to do even with the proper tool. The original rail has a locking nut that pushes up onto it. You need a largish spanner (or, as the Brits call it, a 'spanner') to get it off. I improvised with a screwdriver with the tip wrapped in electrical tape to make it mar less and light taps with a small hammer (or 2 pound dead blow...)
The traditional barrel nut and handguard thingamajig is now installed.
And with the gas block and tube back on. I thought I'd have to remove the tube from the gasblock and had the pins all ready to go. Live and learn.
All in all, pretty easy, lemon squeezy. I had to think hard about the order of nut, thingabajig, and thingamajig spring, but there is really only one way that works. Lining up the foresight to it's original position was a slight issue. Be sure to mark it before you take it off. And air does indeed go out the gas tube in the receiver if you block up the chamber and use a compressor to test it, so I am hoping it is still semi automatic. I ran a patch through in case any moisture got in the barrel.
I went from cleaning in an anal retentive fashion to seeing how much grime a gun can take to back to cleaning frequently. Even on gun that can really take to the grime. But I clean for rust prevention at this point. No one really wants a dirty gun, but everyone hates a rusty one.
I put this pic in to get RobertX to comment.