Help with pinion angle

Hi

Re: BMR adjustable torque arm on a 98 Camaro. With car level and suspension loaded:

Drive shaft = +4*

What angle do I set the pinion to to get -1* pinion angle.

I plan to put the magnetic protractor on the bottom mounting plate of the torque arm as per the BMR instructions.

As I understand the instructions I have to tilt the pinion down 5* from level. This sounds like alot to me. Can this be correct?

No lengthy procedures or methods please, realy just want to know how many degrees to move the pinion from level either up or down.

Thanks JA