I've driven up and down I-5 completely across the state twice now and no cop's ever stopped me for anything about the truck. I don't know about the bumper height, it doesn't seem too high to me and I've lifted mine an additional 3 inches by putting on 46" tires.
Unless you're planning on using the truck for commercial purposes, I highly recommend getting collector plates on it. WA only charges once (some states charge every year) and you'll never have to worry about tabs again. If it's gonna be your daily driver, then this would violate the spirit of collector plates, however as they are only supposed to be used for special occasions.
When I registered mine, it wasn't classified as requiring a CDL.
You might want to check your local municipality if there are any restrictions about where you can park the truck. The m35a2 is sometimes classed as a commercial truck for some rules even if you don't use it for commercial purposes. For instance, where I live, you can't park a commercial truck on a residential side street. I don't know if this would apply or not. I park it in my driveway, but there are some communities in the country where this would still be illegal or a violation of covenants.
This part is just my opinion: Much of the truck may be exempt (or at least get a pass from the State Patrol) from some rules just because of its status as an antique military vehicle. Some rules that may apply to passenger vehicles probably wouldn't apply to the deuce.
Find a bunk, stow your gear, and prepare to get underway 
