The E8000 has a cut on the top of the motor allowing cables run over it. The ep8 is solid. So either modify the inside of the frame or make a cut out in the casing of the motor. Going down the EP81 is expensive. E8000 is less troublesome.
Think getting it serviced first is the best option I’ve...
The motor is working no error codes getting a bit more noisy sometimes on the climbs, done 8k, you have to shave a bit of teh internal frame as motors are slightly different on teh top
I ride a YT decoy mull EMTB with shimano E8000.
I'm looking at replacing my E8000 motor would the upgrade to EP8 be worth it, i don't don much techinal climbing.
@Greg Watts