personally i feel the best preparation i can think of would to be living somewhere in the rockies or up in alaska, to get a head start on the situation you could head out to alaska and get a pioneer permit which basically to my understanding means you go out, build your own house, you are able to hunt any animal you want and you basically live off the land like you would have quite a few decades ago. any apocalypse from there and you are just doing what you have already been doing
vehicles, bobbed deuce for sure with one of the military flatbed trailers, not sure the exact name... i would use it to tow my cherokee around, its a lot "nimbler" than the deuce would be. a good motorcycle would be good as well. again the plan would be to get to a place up in the mountains. with luck/skill you can hunt, if you find a nice valley or meadow you can set up housing and small gardens. obviously there is strength in numbers so first priority for me would be rounding up a few very well trusted friends, as well as anyone else in the jeep/expo community that i have met or will meet between now and then. setting up a small community out there just seems like a good plan, as long as they are people you really trust. we dont want any leadership issues...
anyways back to the vehicles, m35a2 with the multi fuel injected motor, my jeep, i would love to build up an old suburban. i have a 75 c10 but 2wd doesnt cut it and i will be looking to replace it with the same era but 4x4, that would help with transporting supplies/people to the new location. the deuce would be for supply transport as well it would have a decent sized fuel tank in the back, i think i would go with a gas instead of diesel. the deuce can run off it, and its easier to find a burban or older truck with a 350 (mine has 454) than it is to find the 6.2... for parts anyways. my dream fleet would be the m35a2, 75 burban 454/th400, mid 70s k5 blazer 454/th400 (mini burban clone, same parts=less trouble down the road if something breaks) both on one ton axles. cherokee for a lighter utility vehicle. few dirt bikes for the necessity of speedy missions. that is, the fuel wont last so any "missions" would be bulk stock up on ammunition (hunting) canned foods, other non perishables, might as well look for TP to avoid using leaves for as long as possible
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. we would need food processing stuff. so a pressure cooker, vacuum sealer, canning stuff, meat grinder, and a few good knives (of course all of this is mechanical, dont plan on bringing generators cause again, fuel doesnt last and i dont plan on devising the construction of a magnetic propulsion alternator powered generator system (it works but its just alot of work and unless i get really serious about this im not messing with the idea) i would want horses/donkeys as well, makes the hunting easier and if we need to head to town after the fuel has run out it makes that a bit easier. but anyways this isnt about survival plans, its about the rigs and ive rambled on way to much about this so im going to head to bed now...
edit:
tires were mentioned, i would obviously run the proper tires on the deuce but the fleet would have tracks set aside waiting for the event, tracks stored in m101/m416/m107 trailers to be towed behind the rigs, as well as two spares per rig mounted on a cargo basket, RTT's for the trip to the mountains as well as the time being when we set up the housing situation. the tracks are there in case of catastrophic blow outs leaving a rig with 3 tires... the limit travel speeds so used in just that situation, as well as when we get to the mountains, we could travel farther in than with tires, well the travel would be alot easier, especially if in the winter time burban takes the lead followed by the k5 then the cherokee, then the deuce, they would break trail in that order because the tracks leave you with a foot print that exerts 2 ft lbs of pressure per square inch so they act as snow shoes, the burban would dig the biggest rut, k5 would follow up packing it down, and a final pack with the cherokee, then the m35 has to make it through, hopefully with no issues (this is just a theory obviously) im sure i could get tracks made for the deuce but they would be very large and the plan is absurd sounding as it is lol. (this is all just the ramblings of a 20 year old, i dont know everything and im positive there are massive holes in my plan, but i feel like i would have a chance at least, and heck, i wouldnt be out there alone)