How do you remove the doorsills? I'm trying to install new stainless steel ones, but can't get the original ones off. I've tried dental floss but they won't budge.

TIA

 

I replaced my stock C4S sills with carbon fibre.
Get a plastic putty knife about 3 inches wide and work it under the rear edge. Using a saw like motion, push under the old sill to break the seal so you can get fingers under the edge. Lift firmly and slowly as the glue seal breaks.
I used goof off to remove the old glue.
Should take you less than one hour.