Rear axle centerline for 39 Ford?

Working on my 39 std coupe. I dont have a tech manual if there is such a thing, but my question is, is there a measurement reference point on the frame that will locate the exact centerline of the rear axle? Or how would I know exactly where the centerline should be.

The person who owned the car before me, made some rather stupid decisions, and I dont trust where the axle is now. Besides the 10 bolt chevy that is currently in the car is being replaced by a 57 ford 9 inch housing.

The rear fenders were off the car when I got it, so I cant tell if its right on. I bolted a fender to the body before I pulled it and it looked (eyeballed) right. But I am somewhat of a technical minded person, and would like to have an exact measurement if I could.

Any help would be appreciated, or point me in the direction I should go.

thanks!

Jeff

There should be a conical shaped rubber bump stop directly over the axle centerline. If it's gone there should be a hole for the stud mount in the frame.

Thanks Bob, I didnt know if there was a rubber bump stop from the factory. Its there...

thanks for your help.