[basemodele90glazer]

i got a shifter knob from what i think is an e31 and have been trying to get it in my car for the last hour.
the problem is that the shaft that goes into the shifter is a different length than the e90 shift knob.
if i cut the shaft off it wont be able to lock reverse without pressing the button.
is there a way to swap the internals?
should i just cut it off?
please help

oem knob on too
e31 on bottom