If you have a local shop strip and clean the heads and ask them how much they would charge to do it. My local shops machine shop closed so I was forced to buy my seat machine but they used to charge me 8-10.00 per hole. Might be worth checking but I would recommend having them as clean as you can get them.
That is the problem with machine shops in Denver. Way too stupid busy and can't be bothered with a small job. My thoughts are to use the cutter to get close to the diameter I need then use grinding stone to finish it.
