1) No. You must cut away at the other piece of the hopup on the lower receiver.
2) I'm not sure how the 2 piece system works since I don't own any guns that use it but if you take the "C clip" off you should be able to just pull it out like you would with a standard 1 piece. Note the hop up bucking is likely putting friction on the hop up to hold the barrel in place.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE