are those santana-cup-holders?
or like MusbJim use aroll of duct tape on the floorboard.
There isn't much room to put them in a Spyder FYI. You MIGHT be able to stick them in the cockpit bulkhead, but that is an excellent place for the heated seat switches. Or maybe in the inner rocker panels, just make sure they install flush for getting an and out. If I drink coffee in the Spyder on an A.M. drive, my wife will hold the cup or I'll wait until I get where I'm going. Like this Sunday I'll probably hit a C & C event.
You can just use a roll of duct tape, it really works.