did i pull from the right vehicle?

[wazazzle]

I pulled these front calipers from a 87 ltd crown vic. How can i be sure they are the 73mm? I know the 91 have steel pistons typically maked with "s". So, if these are 73mm calipers they'd be phonemic. How do i verify it's a 73? Yes, I've already been to http://mjbobbitt.home.comcast.net/mustang/4lug.html
I just want to make sure.

 

[352Ford2]

measure them they will be 73 mm which is 2.87 inches