Be sure to have $300 or more so you can buy the Naughty Nitewear from Mick & Ralph before going to the Atomic Wrangler.
From there it was easy to make the east gate with less than 100xp because I discovered only Novac and killed nothing along the way. I took the tracks behind Jean's and followed them behind Primm, went South of Nipton to avoid the Viper gang ambush and turned east, then North to meet up with the caravan going to Novac. At Doc Mitchells, set Vigor to S.3, P.4, E.7, C.1, I.9, A.8, L.8, Traits are Small Frame & Built to Destroy.
