Ben,
The top of my hatch measures 24" front to back, and 22 5/8" side to side.
The OD lip in the front measures 3/4". It angles out 1/4".
So, this online trig calculator computes the angle to 19.5 degrees.
Trig calc
From the top forward point of the hatch, add the 19.5 to 90 the angle would be ~110 degrees.
That should get you in the ball park. [img]/images/graemlins/smirk.gif[/img]
Hope that make sence .... - Nick