Trying to change the sights on a P-95 Ruger.
Removed alan plug from rear sight, could not get rear sight to budge with hammer and punch.  Front sight looks like its got two roll pins through it, but replacement sight (IMX Tritium) has no holes for roll pins.

Has anyone ever done this before?

I did some P-89s years ago...same thing.
Take note of location of rear sight, windage wise, to install the new one in the same place, assuming it was sighted in originally.
Taking the slide off the frame, (barrel out)laying it sideways on a solid surface (not on the safety lever) either clamp or have someone hold it in position for a good whack, that should move it. Watch for any springs under tension below the sight.

Drive the two roll pins frome the front sight and tap the blade forward and upward until it's free.
The new front sight has to be drilled through the existing two holes in the slide, for the roll pins to go back in.
You must keep inward pressure on the front sight or it can "walk out" while drilling.
Careful when installing the rear sight, the tritium capsules can break...aim for the lowest part of the sight, nearest the dovetail when drifting.
Good luck on your project.

Anothergene--Man, thanks for your help!I get a case of the instant puckers when I start beating on somthing hard.Its good to know it will move and the other one will go in there.Wonder if I epoxy the front in place before drilling?

I never tried epoxy for holding something like that in place, just a good eye and a firm grip. I don't see any harm in it except when and if removal time comes.