I put a Kawi Dasa in an 09 SJ. Rad Dudes bedplate , cold fusion Yamaha coupler on stock SJ midshaft. Cold fusion kawi coupler on motor.
Option A- Get a midshaft approx 38 mm longer than stock
I went with option B
Option B - Drill new holes in bedplate approx 38 mm rearward. The holes motor bolts to. Front of bedplate needed trimming to clear flywheel housing. Use trimmed piece to fill and weld one area where there is a void in plate so you can drill that bolt hole.
Bolted Sxr elec box straight through bulkhead.