Good way to punch scoop holes in hood???
4 1/4 in bimetallic hole saw. works great. you can also use a 4 in. Make sure to tape it, so you don't mess up the paint too bad.
http://www.mts.net/~hpokrant/Miscellaneous/Hood Scoop Seals.htm
for the rings these seem to be the best and cheapest.
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