That Blair is the hot ticket. It is sold under a few names, including Matco. They should have the cutting tips available in 3/8" and 5/16" The blair tips are much beefier than the others that I have used. Center punch the hole, take it slow and low, keep the tip wet. .......(shhhhh. car talk is sooo dirty). As far as splitting the panels after cutting, trial and error. I had/have a homemade separator that I made from a piece of steel about 1" wide and 1/4" thick I sharpened. Eastwoods and others have a dedicated separator that mimics what I have. Take your time and don't be too aggressive with the chiseling, if you want to keep either panel in shape.