[DanEC]

Originally Posted by Jerry Clayton

driveshaft angles are the angular differance between the pinion shaft,drive shaft and transmission mainshaft--the angle to the ground has nothing to do with it--
Now , having said that, if the only means you have fir measuring angles referances to the ground, you can correct the numbers to what the drive line is----

take the springs off the shocks and block the car/suspension to what you want for ride ht.
Adjust the drive angles---then figure out what distance you have for the spring at ride ht and go from there----you will probably be in the 10 in size

Yeah - you need the angle between the transmission tailshft and driveshaft - and the angle between the driveshaft and the axis of the rear pinion shaft. The angle to the ground is meaningless. Turn the transmission yoke until the yoke arms are oriented top and bottom and put the angle gage on the bottom of the yoke arm and measure the angle from horizontal. Then put the gage on the driveshaft and measure it from horizontal. Subtract the two and your have the front deflection angle. Repeat this for the rear.