Something I need to elaborate on that I forgot to mention last night, but you also need to check is the driveshaft angle, your driveshaft angle in relation to your trans and pinion angle, this is where you want a 1-2 degree difference. On the pinion you want your angle to be to the negative, so pointing down in relation to the driveshaft angle.
So as an example. 7* down on trans, say driveshaft is down 6*, you want pinion pointing up 5* This gives you 1 degree on each joint and each one is opposite of the other so they cancel out.
You can get something like
this to change your pinion angle. They make them in different angles to get you within a couple degrees.