I have one.  It was my High School graduation gift 27 years ago.  Serial Number is XXX604, and she has always been a shooter, never a safe queen until 05, when I got a Stag Model 2 and semi-retired her to the comfy life of a range only rifle, fed only the finest Q3131A .55gr bullets.  I was not always this picky, and my time in the service allowed me to cram many an M855 and M193 (I worked on Range 214 at Camp Pendleton and I spent quite a few weekends with Reserve and Guard units 'qualing and shooting up their left over ammo) down the pipe.) and as such, she is not as pretty as she used to be.  The dents and dings I don't care about, that's character and love and time spent in the boonies, but I would like some ideas for a good cleaning product that will not destroy the finish.  

Second, she is a slick side, and I love that, but I have always wanted to do an A1 upper in the same finish, just because the first 16 I ever fired was an A1 (My dads reserve unit) and later in High School in JROTC spending spring break at Pendleton.  My senior year, we fired A2's, I earned my crossed rifles on a brand new A2 in Boot later that same year, but was issued an A1 when I first got to Guam.  Someday, Ill get a clone of the A1 and A2, as they were issued, but I would also like to do an A2 in same Electroless Nickel as my Baby.  

So here it is, 1) What is the best cleaning product besides soap and water or CLP.  2)Where can I get the exact same finish done to produce a swap out A1 Upper, and later, a complete A2.  Hell, if I like the work done, I may get the A1 upper its own lower, but my idea is to stick with all-Colt parts on that one.  

Check with member hotdog250j,he had someone do electroless nickel plating for a couple of projects.
ETA with thread of his projects> http://www.ar15.com/forums/t_3_4/553433_458_and_223_finally_done.html

NP3+ is supposed to be a better finish than electroless nickel...but I doubt you will find anything that will exactly match your >25 year old finish now

ETA: here's a link to Robar'shttp://www.robarguns.com/precision_coatings.htm
ETA II" do you still have the original HG's to replace those LSO's

Yes, I have the original handguards.  The round things on there now are an old set from Lone Star Ordinance, circa 1986.  You cannot use a Harris Bipod with the original guards, and even though I have an original USGI clamp on bipod, I do not like the marks it makes on the barrel.  So, for bipod shooting, I use those handguards.  Same with the windage knob, I still have the original parts in my safe, as well as the original round front sight post, but I much prefer the square one on there now.  

I guess, in the end, if I cannot get a close enough match, I am going to have to build an A1 and A2 Clone, instead of the A1 upper.  Oh well.  A few years ago, I did see an R6001 in Coltguard.  It did not roll out of the factory that way, but the original owner had it sent back to Colt to have it done.  That really caught my eye and now I need more than just one.