Clear span dimension needed on mid-rise caps - 2nd gen - Snugtop Sport Hi-Liner or other

Hi Folks,

Does anyone know, or can please measure, the clear span dimension at the bed rail/top of tailgate elevation with the cap door closed (cab to tailgate at bed rail height).

I'm looking to replace an older cab high cap with a mid-rise and installing a deck system.
Snugtop Sport Hi-Liner is currently the leader for the curved back glass with a decreased angle to tail gate (most vertical) and the additional strength reinforcement option. The clearance is really the driver on the choice.

My current cap loses ~3" up against the cab with the front mounting lip. I hope to minimize this obstruction and maintain as much of the 73.5" span as possible.

Looking forward to the build out and thank you for the help!

-JT
'05 Access Cab