SHELBY GT 350 Member
Joined: Oct 2010
Location: Desert Southwest
Double-sided automotive 3M tape. Maybe? Velcro certainly won't hold.
You could probably have a shop devise a mount that attaches underneath the fascia or through the openings and wraps up in front of the fascia without actually touching it.
Either way, a plate on front is a plate on front. Might as well drill it and then plug it when you get ready to sell.