It doesn't work like that, pman. The board checks to see if the prongs are jumped only once, during bootup. If it finds a complete circuit during the boot sequence the full auto mode will be selectable. (Or, if the gun was shut down in full auto mode, the semi mode will be selectable) After that it doesn't matter if you remove the jumper, since the gun is already unlocked. That's why you can slip a screwdriver under the grip to boot the gun up in "unlocked" mode without using a jumper at all. You COULD, in theory, install a microswitch for those two spots on the circuit board and be able to push the switch during bootup to enable the mode, but this sort of thing would be useless for cheating; in order to put the gun back in locked "legal" mode you would have to put the gun back in semi-auto, shut it down, release the jumper switch and THEN boot it back up, doing all of which would take at least 10 seconds.
And shame on you, for suggesting a cheat mod.
A little history lesson: this little trick worked great with the old Bushmasters and Defiants. Unscrupulous users would replace the dip switch with a hidden microswitch somewhere on the gun to enable fully-automatic firing when they chose. Some even used a magnetic reed switch and combined that with a hidden magnet in their gloves, which would only make the gun full auto when they, and only
they, held it in certain ways.