BMW Z3 Sill removal and protection
Article supplied by z3cade (Liam)

Jack up the car and place on axle stands
Remove wheels
Remove rear arch liner

Remove kick pannel trim and door rubber

Remove kick panel plastic plug

Remove kick panel by lifting up

You may brake some plastic clips so remove broken clips from holes

Remove front arch liner

Remove screw from front arch, top front of sill (use 10mm ratchet)

Remove three screws for the small side panel, detach side repeater and remove

Get a friend to help, but a good friend not a nutter…

Remove screws from under the sill

Remove screw from rear arch

Remove small plastic trim from inside door and remove bolts that hold rear arch to allow better access for the screw behind it

Remove final bolts from top of the sill that were under the kick panel and remove sill

Clean up box section and check for rust

Treat areas with rust with your prefered products

I used zinc 182 primer, clear Waxoyl spray for inside box sections and original Waxoyl underseal

Treated rear box section

Treated front box section

Sand down any rust found on the sill and treat with your desired products

Now just reverse the removal process and replace the sill, Job done