LST2 Conversion

hi,

i think about a lst2 conversion.
i want use 6s2p a123 batteries, a mmm v3 and a 10xl motor.

here a pic of the motor, i dont know who is the manufacturer:



what is recommended, shall i use the 2speed adapter or the smaller pinion only?
do i have any advantages if i use 2speed?

is there a chance to use the original 2speed clutch bell with an adapter?