I would shoot for .0025" to .003",

3/4 groove King Alelecular bearings are great!

Cheers,

Arnie


67 Cuda 8.48@ 158.7 mph 1.18 60' 2,600 DA(so far...) 70 Super Bee 440 Six Pack 4-speed. 13.2 @ 104 Stock exhaust/Street tires.