I use a BBQ lighter. Stick the front end of the rod out a little and move the lighter in until it begins to bulb then pull the rod back into the sight. For the rear I use a toenail clipper and snip it pretty close to the back of the sight (muzzle end) then same thing, the bulb pulls right in.
I suppose you could use a heat gun or a small butance torch: https://www.harborfreight.com/weldin...YaAqoLEALw_wcB
The BBQ lighters work for me and I always have one laying around the area.