For starters, what's the best way of getting those pins out without damaging the rifle.  I don't care about the fixed sight.

I personally use a 3/32" nail set and a 16-ounce hammer.

For more detailed tips from various members, please check out the following thread:

www.ar15.com/forums/topic.html?b=3&f=4&t=240826

A punch and hammer.  

Have fun!

Torch and a big ass hammer and a punch.
Ok maybe the torch is a little over kill but you may have to heat up the front sight base a little to help get the pins to move but don't heat to much and wreck the finish. And try not to heat the pins them self up if you can. This will help a lot. or i have heard of this also is to throw the whole barrel in to the oven and heat it up to like 300 degrees and then try to drive out the pins. I have never done it that way before like i said i heard of it done with the oven treatment. The idea is to heat the metal and it expands and the pins become looser (not as tight).
E3

hammer and punch

A tip.  When you use punches you will break some sooner or later.  Save them.  They usually break where the body tapers to the actual punch diameter.  Dress that up on a disk sander, do not allow it to over heat.  Keep a container of water handy to cool it off.  What you have now is a great starter punch.  Only use it to get the pins started.  You can beat the hell out of them and they won't break.  Once the pin starts, use the proper diameter drive punch.