We use the black self-adhesive velcro hook and eye stuff from the fabric store. Just buy the length and approximate width you need and throw the hook side away and use the fuzzy (eye) side. Cut to size (length & width) with a razor blade, release a short length of backing material--1/2" to 3/4" and place it in the groove. Then proceed to push it to the bottom of the groove with a piece of wood (half a clothes pin works great) as you pull the backing away as you go. DO NOT remove all the backing and try to put it in the groove. The self-adhesive on this stuff is very, very adhering.
I know going into a fabric store may be to foo-foo for you (send the significant other), but as long as you clean the channel before you start, this stuff really sticks. Works well for most automotive applications--much better than the stuff you buy that requires an adhesive.