My 63 and 64 Rivs use the same key for ignition, doors, trunk, and glove box. When I bought my '64 there was no key for it (the swtich was in the off position and I didn't lock it.) I took one of the door locks to a local locksmith and he was able to use the number stamped on the lock to cut me a new key. It works well in all of the locks.
Perhaps you can get that glove box lock off and have a key made for it; all the others should work then.
Ed
_________________________
Ed Raner
ROA #279
Heartland Regional Coordinator (Kansas City area)
1963 Riviera - Black w/ white leather
1964 Riviera mild custom
1985 Riviera - Dark Blue (stealth mode)
Some days you might have to be the statue, but other days you get to be the pigeon.