Been there many times and am going back in June driving a F350 dullay towing a 43 ft 5th wheel. You will be fine in a 26ft motorhome. Plenty of places to park. Just stay off the Needels Highway and Iron Mountian Road (16A) and you won't have any problems. The rest of the roads are plenty big enough for your motorhome. I see 40 and 45 foot Class a's there all the time. You could even do the needels highway depending on your height. Google it and take a look. Go to Google earth and you can look at all the roads in that area and see that it's not a problem. Have a great trip as this is on beautiful place.