Supertec and 911 Vintage Parts has a kit that includes 6 different shims and two proper gaskets. $ 79.00

The gaskets are
901 105 198 03. they measure .008" The later gasket for mag case and later measure .025 to .040" depending on the manufacturer.

The shims are
901 105 162 01 .006"
901 105 162 02 .008"
901 105 162 03 .010"
901 105 162 04 .012"
901 105 162 06 .015
901 105 162 08 .020"

Thanks I can do some sums.
Lyndon

For those builders unfamiliar with setting end-play on early aluminum cases, it's really pretty simple.

Check the intermediate shaft (end) for damage. It should be smooth. Make sure the plate/cover is perfectly flat. For those of us who don't have a surface grinder, fine sandpaper (320-400) on a flat surface will generally work. If you're fighting deep gouges (not uncommon) heavier sand paper followed by the finer grit, may be necessary. Don't be afraid to keep sanding . Plate thickness (within reason) is irrelevant.

Install the cover on the studs and tighten it gently. This first stage it to insure that the intermediate shaft is pushed all the way in. Loosen it, then tighten finger tight without gaskets or shim.

Measure the gap between the cover and case with a feeler or two. You can measure it in multiple locations to get a consensus. Add your desired end-play number to your consensus measurement and you're there.
Keep in mind that even the very thin gaskets will crush about 10-15%.
We've had our best success using a non-hardening sealant on the shim and gaskets.