I changed the front tires on the QL 1000 to 18 x 7.50 x 8 to match the rear 26" tall tires.
The 7.50's are the exact width of the 16 x 6.50 x 8's I took off so there is no rubbing when turning.
After changing the tires I tried it out by hauling a couple loads of firewood for the Cub shack.
I had to keep the trailer loaded front heavy to maintain traction coming down the mountain.