I'm finishing up my five lug swap and hit a wall. On the aluminum 911 hubs, is it proper to use a split washer on the aluminum hub when bolting on the rotor? If so, should I run the bolt through the hub first so the split washer is on the rotor side instead? I'm worried they will mar the aluminum.

I use a flat washer and non-locking 8mm nut torqued to spec.

I use spring washers no split washers.

2 900 075 079 02 Hexagon-head bolt 10 914-6
M 8 X 22
3 N 012 241 1 Spring washer 10 914-6
B 8 X 15
4 900 076 025 02 Hexagon nut 10 914-6
M 8

Spring washers are correct. The bolt goes through from the rotor side with the nut and washer against the hub.
Bruce

Thanks everyone. I'll be on the hunt today for spring washers.