High pinion crate axle pinion angle?

I'm planning out a project and am trying to get my ducks in a row. My plans are a rear-engine rock bouncer/crawler with Torq Super 14 axles, front steer only.

Talking with them, they said the Super 14 can be run with the drop-out third flipped to high pinion in a rear engine application.
They set the caster between 3 and 5 degrees but need to know the pinion angle because the C's are press fit to the axle tubes before welding.

Reading on Pirate4X4 it seems the average pinion angle in a high-pinion situation is around 8 to 11 degrees, but these are mostly Ultra 4 guys.
http://www.pirate4x4.com/forum/general-4x4-discussion/1067938-survey-whats-your-pinion-angle.html

I'm having this buggy built so I'd like to send him a crate axle complete and lead time is always a factor.
Powertrain is as follows:
LS1 (450-500 hp range), TH400, Atlas II 3.0:1 driver's side drop (passenger drop rear when ran rear engine) Front axle chunk will be centered.
43-14.5/17 SX non-sticky tires.
114" wheel base max with around 22" belly height is the goal.

Super 14 pinion shaft is 1.75" above axle center line.

Here's my question and don't slaughter me:

1) For the bouncer guys with high pinion axles, what pinion angles are you running on average?
2) How many degrees from perfectly straight can it vary without causing problems/vibrations?
3) When using a Ford HP 60, Rock Jock 60 or similar axle is it common to cut and rotate the knuckles to correct pinion angle-caster relationship or is it sufficient out of the box?

Any help is appreciated. :****:

Can't help here, but cool to see someone trying a rear engine bouncer!

Pinon really don't matter because you wont have drive shaft problems caster is what you need to watch I try 2 set it around 6 good luck I think a mid engine would b cool