You don't have to be artistic in getting the old ring gear off. If you have an oxy/fuel torch, just hit one spot with the fire and make a few sparks with the oxy. If your cut is not not completely down to the side of the flywheel (I prefer to get close, but not completely through so I don't scar the flywheel) then take a cold chisel and a few dozen raps with the BFH to split the ring gear. It doesn't take too much effort.
As to putting the new ring gear on, it needs to be preheated on its full circumference. I have not had any luck with the BBQ grill and a measured 500 F temp. The flywheels I have replaced RGs on have a larger diameter the RG has to go over and then a smaller diameter that the RG fits into, so I have had to make the RG excessively hot to get it big enough. The last one I did, I put the FW in the frezer overnight and then submerged it dry ice in a styro cooler for a few hours to get it to shrink somewhat. I still had a tough time getting the hot RG on. Fortunately I had a few extra hands from a couple of friends who stopped over to witness the RG installation.
If you get the RG fully red hot, it loses its hardness and is quickly (1 or 2 years) destroyed by the starter bendix.
Other guys on this board have described the installation process as "heat and drop". Possibly I had a few RGs made in the land of Never Right, as I quickly discovered they were not truely round, but somewhat egg shaped or elliptical, and took a lot more effort to install.
Paul in MN