Hello all, I have a 12 bolt I'm getting together for a '68. The housing I found had no main caps with it . I scrounged up a set of caps and with a little tweeking of the bolt holes the caps centered on the parting line. On the passenger side I came up with 3.062 I.D. on the drivers side I have 3.060 I.D. I believe the spec for a brand of aftermarket caps calls for 3.063 +/- .001 in. I'm curious if the .002 undersize on the driver side cap will be a problem

The bore should be about 3.062. The race should be 3.0625. This gives a light press fit to hold the race in place so that it doesn't spin in the bore. The bore needs to be about 3.062 to hold the bearing. I think that 3.060 is going to be too tight and may crush the bearing race a little and cause it to be out of round. You might cut some .002 shim and put between the cap and the housing to open the bore up to 3.062.

Freddie, good idea on the shim stock. I tried .003 shim stock and came up with a tick over 3.062 I'm thinking good to go. Now scrounge up the rest of the peices, and put it together.