I need a measurment from a trailing arm truck.

[68LSS1]

I'm getting ready to slide the 8.8 under the truck. I need a measurment if possible from someone that has a trailing arm suspension. What I would like is for you to drop a straight edge off the frame above where the trailing arm angles out and then measure how far that is (outside of frame to oustide of trailing arm). I'm guessing it should be around 3 1/2-4". It should be the same on both sides but humor me and please check both. The saddles I got I had to open up and the fit is really tight and if I get the angles off the trailing arms will be binding slightly. I would like to make them fit a little loose and just center the rear and then move the trailing arms to were they need to be. Tighten up the U bolts and it should be good until I can get weight on the truck to set the pinion angle before I weld them up. TIA