edit: WHOOPS! Will not work, it is an "E" reach, not and "H"
I use these on my KTM to clear the fuel tank.
I do not think there is a BR8HCM, but it would be what you are looking for.
Denso makes short plugs as well, Denso IWM01-29 was a replacement for the BR8ECM.
Brace yourself for the price!
(Previously posted, NOT VALID)
Use a BR8ECM.
Pricey, but shorter on the top side for more clearance.
The inside the cylinder part is exactly the same.
Steve