There was a brand called GlassTite (I think) that was tall enough. It was the only one I could find that worked (without having to compress the suspension to get thru the door. The downside was that it was expensive (like 50 to 100% more than other brands. I sold it when I build a custom flatbed (to haul snowmobiles).
we ride with a guy who has a full size dodge with a cap,doesnt look any taller than normal,he must compress the front and rear to get it in,Ill ask him
We run a "high rise" tapered A.R.E aluminum utility cap with double entrance doors (like a van has) on a F350 Super Duty Crew Cab. It's tall enough at the entrance doors to get a bike in without compressing the forks (like a full size van.)
For better aerodynamcis we had it built with a front taper. The shell starts about 2 inches above the trucks cab and rises about 15 inches over the first 3 feet then it contiunes flat for the next 5'. You can push the bike all the way to the front without the handlebars hitting.
We also ordered it with two conventional 8' long fold up windows on both sides so you can access the full length of the truck bed. We can easily fit 2 bikes in the bed and close the doors. We can also get in 3 bikes if we have to but it is tight.
We also ordered it with security screening (in front of each window), heavyduty utility locks and had the roof lined with carpet.
I was at the alligator enduro a couple years ago and saw a guy from NY that took his front wheel off and put on a small bicycle wheel to roll inside a camper top. Sort of extreme but it worked.