can he fix my pants? they're a little long.Actually it is a travel tailor.
I would say to ask the State Police in the states you plan to travel to rather than post the question on an interweb forum full of people who may or may not know.
Especially since none of us will be around at your court appearance if you get arrested.
It only has to be secure during interstate travel, and even only then if the firearm is crossing into hostile territory. In Indiana he can carry it loaded in his vehicle. To answer.your question.about.vehicles without a trunk.... the federal safe passage law tells you what you need to know.
"...That in the case of a vehicle without a compartment separate from the driver’s compartment the firearm or ammunition shall be contained in a locked container other than the glove compartment or console."
18 USC § 926A - Interstate transportation of firearms | Title 18 - Crimes and Criminal Procedure | U.S. Code | LII / Legal Information Institute
There are numerous options in an RV for interstate travel.