I would take I-10 east to Palm Springs, then SR-62 to 29 Palms, Amboy, & Needles. Stay in Needles or Laughlin. Proceed east on I-40 to SR-64 and main GC entrance. Backtrack to Kingman and take US-93 to Vegas via Hoover Dam; or SR-64 to Flagstaff, SR-89 etc. back to Vegas via Mesquite. Winging it as far as places to stay is part of the fun. Pick only motels that advertise their rates on the sign. Fuel up at every larger town (Needles, Kingman, Flagstaff), as fuel prices in the MFN are usually (even more) eye-popping. When driving at night, listen to Coast to Coast AM and Native American dance broadcasts; stop to stargaze.

Wear good sunglasses; carry water and food. See you on US-66!
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