Your number sound about right. "
Overall height closed with low profile AC according to customer portal = 79.5” . I have a 2720 with a lift kit and the full size AC with 14" tires and I'm around 91. I know the low profile AC is much shorter so I don't think the 92" number is correct. I think that number is with the full-size AC????? Per the web site it's 79.5 with the low profile AC
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The TM factory can at time be hard to reach, but most of the time they are very responsive, very informative and nice people. They do run a very lean shop, so i'm thinking its vacation time. The times I called, I had very good success. I call and left a message with Ed Lytle. He called back within one business day.
An option you might want to consider is a 2619 with a swing hitch and low profile air. I think the configuration is nicer. I think the length is about the same as the 2417 when you swing the hitch. It 19 feet when towing, but right around 17 feet when the tongue is back.
Height concerns: The normal garage door header is designed around 92-96 inches high. My header is 93.5', You should measure the header opening, many times the door is not adjusted correctly and can be rise higher and should by design be higher. As a test, if you push it up, will it rise higher then the header? If that is your case, some people will just use a 2x4 to hold the door up when putting the camper in the garage, Several years ago before I bought the TM, I adjusted the torsion springs on my door so I have a full opening when I replaced the cables. DYI adjusted is not recommend if you have not done it before. A door repair shop will do it for around $100.
Rear hitch. I'm sure other will chime in. I don't have one, but from what I have seen it looks like they do not extend past the rear bumper when the bike carrier is removed.