Our team tried out these snap slide latches for the 2016 game and had a good amount of success with them.
http://www.mcmaster.com/#standard-draw-latches/=12g6itm
You bolt the pin to the top of your drive base frame and mount a piece of angle aluminum to the inside surface of your bumpers to mount the latch.
No tools necessary to take on or off the bumpers, no nuts, bolts, pins etc. to drop. Mounts and unmounts bumpers in a matter of seconds.