I SUV Camped at Lake Powell last October while the Wife was Cruising with a gal pal. Me and the Pooch had a blast for >1 week. The other Threads below likely have more pertinent info re: TT and/or Big Rig info.
I 4WD'ed it out of Big Water UT, just over the State Line, up toward the Escalante Staircase. Right at that turnoff, there's BLM info at the Ranger Station there. Other than crossing a shallow stream on gravel immediately north of Big Water, it's a very reasonable, County Road-type of drive. At the forked 'turnoff' to the East and Lake Powell ~12 miles in is where you'd want high clearance and 4WD IF it's dry. You cross over umpteen lil washouts; no problem when dry [it was]. Several 'Gully Washer' Storms hit the area hard ~1 month earlier.
The Lake level was the lowest since 1969; down about 75' from the Dam Spillway 'top'. I Dry Camped a few hundred feet back from the famous 'Alstrom's Point' from where lotsa pix are taken. Small Rock Cairns mark the endless turnoffs; it's somewhat-easy to get lost. It was a 'Thelma & Louise' drop of ~700' to the receded water. I took lotsa of pix from this exact spot, but didn't have all the Filters and Photoshop effects this pic does:
Alstrom Point ~ Lake Powell
There's a Verizon Cell Tower on top of Navajo Mountain at the rear left of that pic, so there was perfect Mobile/Laptop connectivity. Though ~20 miles in off-Road, Page AZ was line-of-sight, and I was under the flight path of small Planes leaving Page to the north. I texted my coordinates to a pal when I moved around [not much].
As you may know, there's few Roads to the water, irrespective of water level. I Bookmarked BLM Land in UT; around Page AZ; and south at the fantastic 'Lee's Ferry' Campground right on the CO River. One gal had been going there for 30 years.
'Slot' Canyon Tours are at the S.E. edge of Page:
Slot Canyon Tours
'Google Earth' provided excellent recon 'flyover' pix in advance of travel, and elevation info. The 'Panoramio' function linked there is a good way to see uplinked Tourist pix. There are also links to Reviews and all sorts of useful info.
I like 'Weather Underground' for weather info.
Anything you'd want is available in ~7,000 person Page, and folks were great. Super WalMart was kewl with Lot Camping there.
Indian Nation Land is all around, with separate Laws and Legal System; of note to those of us who Concealed Carry and/or try to tread lightly.
Stunning scenery. We'll definitely head back with our newly-acquired lil TT.