wantaTD wrote:My plan so far is to leave the 80 inch wheel base. With 67 inch wide sidewalls...
By this, do you mean an 80"
track width, or perhaps 80" between hub faces (the same thing as track width if the wheels have zero offset), or maybe 80" overall width across the tires?
Wheelbase is from front axle to rear (doesn't apply to conventional trailers), and track width is between the tire centres... lots of people seem to confuse the two.
At 80" of track the trailer would be clearly over 80" wide, triggering the lighting requirements which madjack mentioned.