mk8 replicator 2 extruder base REMIX

i've printed the extruder upgrade for my rep2, but after some prints i got some problems with filament, the pla warms and warped so the spring tension can't pull out the filament right as before.

i printed also in abs but even the same problem.

i didn't buy the upgrade from Makerbot, so i test some prints with mod and this is the best i've done.

i've just print for a couple of week and prints are excellent!

the mod consist to put a M3 nut in the left hole (right if you want to print