Hey Rod,
Have a look at the front intake/front drive unit from Harrop. I believe it eliminates the clearance issue in the back and it is much more user friendly with regards potential repairs or service. I have the same unit as Jeff and had it not been for Brian Thomson -- a $24 seal would have cost me round ticket to Australia to had repaired! Where as the new unit is much easier to separate if you have any issues.
And I believe Brian is the only one this side of the world to have one of the new Harrop units, not to mention the sounds pretty bada$$!
https://www.youtube.com/watch?v=2fkOOEIW02A