I’m installing a couple new solid core pre-hung oak doors, which I got prefinished. I need to cut one of the doors down to fit the RO I have to work with. I got about 1/2 of an inch into the cut with my 6-1/2 inch circular saw before deciding I didn’t have a fine enough blade. Ran over to my dads and borrowed his 7-1/4 inch saw with a fine blade but it’s dull enough it’s smoking. What should I end up getting? 40 tooth? 60? Something else?