It took a little grinding with the dremel, but it wasn't too bad.  I found that only the rear part of the handguards really interferes with the A.R.M.S #38S-EX.  So if you decide to do this yourself, don't grind away too far forward!  Keep testing the fit until you get it just right.

Can M4 hand guards be purchased straight from Colt?

I don't know.  I got mine here: www.ar15.com/forums/topic.html?id=84183

Tanks, I'll have to talk to Pete.  The reason I asked is because I got a set from GunSmoke used, although I don't recall them being advertised as such.  Anyway, my M4gery is mint except the handguards, and I noticed yours look a little nicer than mine.  BTW, were they tight as hell going onto your new Bushy upper?

They weren't tigh at all...after I shaved some plastic off the back end  Just take a dremel and shave about a dime width's off the end closest to the receiver.  The bushy handguards that were on there took about an hour and lots of cuss words to remove.  After I shaved the Colts, I took them on and off about 3 times with no problems.

Let me say this, my Colts are on, and have been on for about 7 months straight.  I haven't even bothered trying to get them back off.  I'll give it a go one of these days when I have nothing better to do, and don't anticipate having to use my thumbs for a few days .  I had no trouble getting the Bushmaster shorty guards out, as they were so flimsy.  I like how solid the Colt guards are, and they're in there so tightly that they don't budge at all.