Mike
I just recently bought a 25' enclosed trailer for the GT, however I needed it to do double duty as an ATV/Sled hauler. The deck height is a little high as it is a "combo" trailer and I had to raise the deck a couple of inches to reduce the inside height of the trailers wheel wells to allow the GTs door to open. I installed a 54" escape door over the wheel wells to fully open the door of the car to allow me to drive it in. As well, I added a winch plate in the front to allow for winching should I choose to go that route which is important if you plan to load solo IMO.
The interior height of the trailer was raised 1' which in turn allowed me to make the ramp 1' longer, reducing the ramp angle for the GT.
E-track was also installed center line of the GTs tires for the entire length of the trailer (excluding v-nose), additional interior lighting and 2-110V outlets
The ramp is slightly to steep to load the GT as it sits, however I got around that by raising the rear wheels of the truck which in turn lowers the rear deck height decreasing the angle.
Sorry for the ramble, hope it helps. Any questions shoot me a message. I can send some pics or blueprints if you like as well.
Steve