ut oh...notch question!

[lotussutol]

I am going to be notching my rear on my 55 chevy truck. I forgot to mark where the rear and frame come into contact.

Does anybody know where the frame and rear come into contact so that I do not have to put the rear back on the leafs and mount them to see where they hit?

I have the stock bump stocks taken out and can use the center hole of the bump stock as a reference point if need be.