This is in many ways turning into a restoration job, which for the price and age of the car is not unexpected. While replacing the front wheel bearings in the Ocelot which are from a Triumph Spitfire I found the brake discs bolted to the aluminum hub with 8 ea. 10-24 bolts. The problem is that on one hub 3 of them are stripped and on the second only 2. Obviously some repairs/upgrades are required. My first thought was to use some 10-24 helicoils and say its already 50 years old, this should be good enough. After much reflection I think that the best way to insure reliability and safety would be to drill out the brake discs and go up to 1/4-20 helicoils or timeserts using Nord-lock washers. Another consideration is age and wear on the hubs so replacement may eventually be required. I don't have helicoils of this size and have never used Timeserts(more expensive) so don't know which is better for this application, and am interested on comments to my solution as I am not familiar with current practice on attaching brake discs to the hubs.
BTW, the brake discs are about 9.75 dia and about .280 thick and the calipers are currently Wilwood Dynapro, I have two other sets of uprights with two different caliper attachment arrangements so the Wilwoods are obviously not original.