Ambi-Saftey /Easy to Install?

I am left handed and wish to drop in an ambi-saftey into my (2) AR-15 rifles.
I have a Bush Master X15-E2S Carbine and a pre-ban Colt Light Weight Sporter.
I am looking at units from Rock River Arms as the securing allen screw is on the shaft of the saftey which would put it inside the frame.
It is decscribed as a "non-gunsmith" install.
Can anyone comment on that?
Also, the Bush Master looks very straight forward but the Colt has a metal block stamped "Colt" above that area (behind the hammer) so I am concerned that this might not be something I'd want to tackle on the Colt.
I am mechanically inclined but am definitely not a gun smith.
Any comments / recommendations would be appreciated.
Thanks!
-Russ
ABQ, NM

I usually don't post here since I don't own an AR15 type rifle. I am a lefty and have always found the safety on M16-AR15 rifles very lefty friendly, I simply operate it with the thumb of my left hand. I don't have especially large hands either. I have found recent US small arms very lefty friendly, especially the M14 and M16 weapons. The M1 a bit less so.

Surprisingly I find the safety on AK type rifles easier to use left handed than right handed. I simply carry the weapon with my non shooting (right) hand against the magazine and my thumb resting on the end of the safety.

I put one on my late 80's Colt. Took about 5 minutes. No problems.

you simply loosen the pistol grip - carefully as to not loose the spring and detent that hold the safety - pull out the old , slip in the new and screw on the left side , reset the detent and spring and gently refit the pistol grip tighten the screw and your done - i just put one on my daughters AP4 , it took about five miniutes [i fumbled around with the detent and spring of coarse]

i was going to stick the other one i have on my carbine , but after handleing hers , i find it a PITA for my right handed hold