From what I read a driveshaft yoke should have minimum of 2 inches of spline engagement with trans output shaft. You can measure how much of yoke is sticking out, pull yoke out of trans, then based on length of yoke determine length of spline engagement.
Your pinion angle should be in the 2 to 4 degree range. Pinion and driveshaft should not be aligned. Have you measured angle of engine trans and then measured angle of pinion?