I have posted a picture of this tool many times here because it works very well and takes very little skill to use, even by yourself.

It cost about 29 bucks from any auto parts store, E bay, Amazon etc. It uses specially braided brass wire to cut right through the sealant with a sawing action. The brass won't hurt the glass and bends very easy around the glass. This stuff is brass wire braided and not piano or guitar strings. You can buy just the wire separately, but the T handles are very handy as is the tool to push the wire through the sealant to get started. It's made just right as to not crack the glass getting it in to start. Worth 29 bucks!

I have removed front and back glass out of 3 challengers and have never come close to breaking any glass. I have used this tool by myself, it is very possible to do it by yourself.

I also used this tool recently to remove the glass out of a F-450, it works equally as well cutting out glass in urethane sealant.