Run your lowers parrallel and your upper like /| and it will be fine. It's been done many times before.
I think you need to do some more research on rear 3/4 links on Pirate and you will see the light
You might also consider swapping the orientation of the rear trackbar so that the axle end is on the passenger side like the front. I seem to recall some discussion with regards to the front and rear trackbars being positioned in the same orientation, I just can't remember if it's a good thing or a bad thing. I'm pretty sure it would be fine though, and then your panhard and upper link mount would be in the same place.
I just don't like radius arms in the rear, I've heard too many bad things about what they will do to your handleing and trail manners to even consider them. I think I would run leaf springs *gasp* before I did rear radius arms.
