I tried that too. It's both the front and rear. I'm going to pour a liquor drink, and try the lube, and "tapping" them on from the rear...IF THAT DOESN'T WORK, then I'm going to sell, sail, cell, sale them as "like new" on ODT for 2X what I paid for them. Amen!
I have a Ruger AR556 and bought some Magpul MBUS sights. Dang things will not go on the rail. I've seen some folks suggesting to "tap" them on using a small block of wood and mallet. Anyone ever done this? Any problems if tried to do it? Any suggestions?