02-07-2020, 06:37 PM
bought a cheap UK Sealey set to start, and punched the centre of the two manifold studs. Feel soft enough. Realised that the LH drills are quite flat ended, so am going to have to open the hole out a good deal at shallow depth before the 3mm one will actually catch and stay central. So I see one does need them from 1mm upward to start applying the correct turning force from the beginning.