Yes, you said you measure the nail or pin front and rear, but it still does not eliminate the problem of how to measure from one pin to the other in a straightline with the frame and suspension in the way.

And the other poster is correct, you can't lift and then lower the suspension and get an accurate measurement, without the roller plates under the tires. Lifting the suspension pulls it out of wack, and then sitting it back down leaves it out of wack unless you move the truck forward and backward.



If I could think up some way to mount one of those laser levels to each rim, I think you could do a pretty good job with a setup like that.