You need a 38mm hole saw & a 600mm extension or 2x300mm & cutting/tapping spray. Check your chuck is big enough, I had to borrow a variable speed drill.
Drill very slowly with frequent application of cutting spray. Dont pull out to check progress as it will be hard to relocate the cutter. Neither of the discs I cut broke off but bent over. No rattles so they must still be there. I only needed one cutter but others needed one per silencer. This needs patience as progress is slow.
I'm pleased with the result, car seems to breather better & I'm considering a Garage 56 air cleaner but £200 is a lot for what it is. Yes it will be louder but at steady speed hardly more noticeable so not likely to wear you down on a long journey.
Tim
