I clearanced my stealths for 1.6’s last year. I don’t think a small tool like dremel will be what you want. A bigger tool not only will have the power you need, but I think it will be easier to hold steady and be consistent with. I used an electric die-grinder with a variable speed controller, both from harbor freight. They worked great. I also bought a burr kit from from Harbor freight, decided on a shape that gave me what I wanted and used WD40 as a cutting oil. It went much faster than I anticipated.

Now the part that may make some gasp, As I assume this is not recommended: I did all the cutting with the heads on the block, in the car. Call me lazy; call me cheap, but I just really didn’t want to pull my heads for a second year in a row. I knew I was taking a big chance, but once I had the valley blocked off with tape, paper, and rags, I was convinced I could keep debris out of the engine. Once I had the grinding done, I blew the heads as clean as possible with air before exposing the valley. then used atf to rinse and clean them real good when done. I then put assembly lube on the cam just to be sure upon startup, and did a series of oil changes until I was convinced it was clean.

My project turned out great, and a substantial performance gain was realized.