Hey guys i want to shoot for a 2018-2019 GTR i make 72/yr at the moment and my DTI will be at 0ish in the next few months and my scores should be in the solid 770s i want to finance for 84 months with the lowest rate i see people getting 78 month terms at 2.74% o_O help!! 
How much are you putting down?! If OP has 0%ish DTI then so what if they want an expensive vehicle lol....that will basically be their only bill.....You definitely want your AUTO FICO to be over middle 750's if possible. That will help you to get the absolute best rate but I would definitely try through NMAC since you are wanting a Newer GTR or your Bank/CU sometimes they will offer really great rates for more expensive vehicles but ask what yours are before opting for those hits. If the bank/cu is to high then try with like I said NMAC for a New GTR or you can try online lending for luxury vehicles or more expensive vehicle loans I think there are some that cap out at like 70 or 80k BUT some will allow up to 200k plus so read into that as well.
It's always best to put cash down especially if you are doing a larger amount vehicle. That will open the door to better rates/terms.
Will you be trading your Hellcat towards it?
Then I def. stick with my original statement. They recommend (especially if you got the Hellcat New with no roll over) trading/upgrading at the 1 year no later than 2 year mark so your car still has the best value. If you kept low or lower miles on it even better.
Another Side note is if your numbers do hit where you want next month I would DEF shoot for it in December or end of the month (last 3 days if you are wanting preowned but NEW will get you a better deal if you are ok with NEW 2019 ((if they have any left)) or 2020) since December likely will hold a better deal/special than January but you can always check with what promotions they are offering at the dealership as well and go based off of that. If they aren't offering anything great on the GTR december, wait it out for the best deal for you if you can possibly wait for a 0% offer to pop up I would EASILY go for that one as that would help you out more. You can frequent their site or even call in to ask if they are offering that if you finance through (whatever finance) so for example like I work for Chevy so if they offer 0% it's through GMFinancial so I'm not sure if NMAC does offer 0% promotions but Nissan will be able to confirm that with you