I live in G and have been doing the backcountry thing here for half a dozen years now (still a rookie I know) I'll throw out some general advice and if you get some more specific questions, PM me because I'm not going to put anything specific here.
- Get in shape now. If you haven't already started you're behind the ball because this is a very physical hunt unless you stick to the desert. Last season was my wife's first year as a resident and we put in well over 20 mountain miles before she got her buck. It was 3+ miles in. (side note: good boots don't hurt but need broke in as well)
- Get/borrow the best glass you can. It's big country and being able to determine if a buck is 1 you want to pursue can be a big decision. We spotted my wife's buck from about 1.5 miles away but to reach it required over 2 miles of hiking with over 1,000' elevation lost and gained.
- Stick with it. My wife missed a good buck on day 2 and didn't get another opportunity until day 7. That's not to say we didn't see bucks, just not bucks she was willing to go the distance for.
- If at all possible, get a buddy to tag along. There's countless ways that country will kill you. With or without a buddy, try to get a Garmin inReach, Zoleo or other similar device (you might even be able to convince mom to get you 1 for her peace of mind). I personally use the inReach and it saved me when I blew 2 tires in 2 days and no longer had a spare.
- Practice with your rifle and know your limits. I spend countless hours and rounds getting ready every year and honing my abilities. I would not recommend stretching your .243 much beyond 350-400. Also practice shooting how you will in the mountains; I can tell you for certain there's no shooting benches up there so be ready to shoot sitting/prone from your bipod/pack/etc.
- Get OnX or GoHunt so you can download maps to your phone. This allows you to mark trails, deer, places to scout, location of hanging meat (if you harvest), etc. so you can follow up as needed. If you don't get the chance to spend a significant amount of time in the area ahead of time this will be invaluable because things change a LOT in the dark and it's easy to get turned around.
- If you do harvest expect to have 70-120# of meat to get out along with the head/cape and whatever gear you hauled in. You will need game bags that breathe because that's not a 1 trip solo proposal unless you're a really big dude (or shoot a really small deer). You will need to find a shady cool spot to hang meat because temps still get into the 70's in September during the daytime most years even at 8,000'+.
- Have fun! It's a sad reality but it'll likely be 20-25 years before you get enough points to have a chance to draw this again. Point creep is carrying the unit about .5 point higher every year and you can only get 1 point a year so it'll be a while before you catch up (if ever). It's amazing country that I really wish I could post pictures of but due to the extreme amount of work I've put into finding my areas, I simply can't share it with anyone outside my closest circle of friends and family.
As was already mentioned, PLEASE PLEASE PLEASE keep as much specific details as possible to yourself after your hunt. There are many of us who put in more effort than can be imagined and all it takes is 1 careless post to ruin a spot for us. I do deal with minor pressure every year but my spots aren't so remote that others wouldn't be all over them if they only knew.
Good luck!