I like the big vehicle plan except for a few details. Number one is the single braking circuit. These things have non redundant brakes, so unless that is remedied, I've have reservations about this especially with someone with only a surface knowledge about the nuances of braking (as opposed to someone with a real functional knowledge of the brakes, who knows what's broken when they step on the brake and it goes to the floor). This is pretty rare, but could be catastrophic.
Also, first time drivers are one of the most accident prone groups out there, and I'm not making any judgement on your young driver. Since the deuce fills up almost an entire lane with VERY little wiggle room, I won't even let some of my friends drive mine unless they have previous experience driving a big truck. You have to plan a buffer zone all around you.
I'd look for an older Pickup - more maneuverable, more agile and able to actually AVOID accidents rather than just "win" them,
I just think back to Sunday. Some driver ahead of me slammed on their brakes to avoid an animal, and then just sort of sat there in the road, slackjawed. Had I not laid on the air horn to awaken them and also stood on the brakes, I would have come quite close to hitting them.
Throw in split rim wheels, and unless you are going to dedicate a few weeks at least to teaching your son the ins and outs of the vehicle itself, I'd choose a slightly less operator-intensive vehicle.
You gotta realize that this is coming from someone who drives a full hyraulic-steering vehicle on the streets regularly. Maybe I'm a worry wort, but putting an inexperienced operator behind the wheel in a deuce worries me.
Oh yeah, did I even mention lap belts aka bisectors or lack of rollover protection?
Welp, this gives you a short list of why this plan is a bit concerning. If you can "hang" with this list of concerns, then I would go ahead with this.
Your favorite wet blanket,

Bob