For several years in the 90s I used to drive around with an old 19" color TV on the back seat of my car. I actually caught a guy trying to steal it. In the trunk of the car was a 2600 and some games in a paper bag.
How did you power it? Are there battery packs that accept standard AC in? Or did you use a converter for the lighter plug? I'd buy a van and put a Commodore 64C with monitor and disk drives so I can play Test Drive while I drive!