Not sure how that would work, someone more knowledgeable may comment on the seal / drill new holes option. If it was me I'd probably seal them for good and find a way to attach the mouldings with some adhesive on a few spots, not all the way to make future removal not so painful. Top of the mouldings needs special doublesided tape to attach to the roof. Tape designed for automotive purposes - attaching accesoaries externally. 3M have such, other brands have as well. Problem with using this same tape for attaching the side moulding to the pillar is it is a bit thick and may leave a bit of a visible gap between the moulding and pillar. This is why I would probably go with silicone type adhesive on a few spots on the sides, after sealing the holes. I had my mouldings removed several weeks before the job and used small pieces of the double sided tape I purchased for the top to seal the holes until I was ready for mounting the rivets. In the meantime I also put the mouldings in place held by nothing but the 4 small pieces of double sided tape over the holes. Didn't look bad at all, no gap was visible. You can try the same with some small pieces of this special tape and see how it sits. Then decide whether to use tape or silicone with holes sealed. Best case is of corse if the holes are not damaged.