The epoxy covered plug is the full load stop. Best way to deal with it is to pull the map sensor apart, make a slot in it with a hacksaw & then screw it in. I'd then drill a big hole through it so that you can put it back where it came from & adjust the small entire range screw without having to remove the full load stop every time you want to tweak it. I'd start by turning the range screw in an 1/8 of a turn & compensate the full throttle mixture by turn it out the same amount. You can lean D-jet cruise mixture out a surprising amount & save some fuel.