IMO, I wouldn't waste my time or money on an alignment till I had new tires and balance them, along with a GOOD check of all steering components and suspension. Anything out of specification gets new. All these parts work in concert. Just to many wear items to try and compensate for. IMO
IMO as a hobby and weekend cruzer (if that's the case, not this daily driver stuff) take it in logical steps as your wallet and timeline allow. IMO, I don't see how a shop would even want to mess with setting up a complete alignment do to time involved, learning curve (unless they are Humv experts) add in a couple rusted up bolts, another couple hours of &#^%%* words = $$$$ and you get a printout that says "SPOT ON" till something else wears out. (nothing new on an old HMMWV, unless you put it there)
IMO, take in steps, A few miles in between say tires and balance, getting on to joints and any wiggle / wobbles and then here's the fun part and money saver... DIY.
It's straight forward wrench turning with a little head scratching, reading right out of the TM's. Build it full on tactical load carrying or modify the numbers for civilian street / off road stance. For me (I get it, not everybody is me) It was a little intimidating at first. After a couple of hours of adjustments, it all started to make sense. The few more hours dialed it in and new muscles working the floor jack. No fancy computer / tools and you see it happen, learn it and no real $$ cost.
If you remember I had changed everything that moves, turns, holds, swivels, springs or shocks... from the frame down. The biggest headache was a boat load of rusted bolts. (150 bucks worth of new grade 8's)
IMO, At least "shake out" all the easy loose stuff. DIY toe in front / toe out rear. Figure your load needs and work out the shims requirements. (Note: if a civy road warrior a bunch are a coming out)
Lot of work and doable on a flat driveway. Lots of IMO's...MY BAD. Nothing personal to anyone. My story, I guess is I like to encourage fellow hobbyist to dig-in. GOOD LUCK.
You can do-it, and I only used the TM word once, CAMO