rc18 - Ya - 1/2" duro on the front and 3/8 " on the back with a 1/32 wire axel and landing strut would be excellent. Below I've piced my latest changes and the takeoff track i made (since I can't find my car track). I decided to elliminate the spacer because I wanted to increase the width between the wheels to 1.25 inches to give greater takeoff stability. By doing that I automatically clear the planes undercarrage. I made the whole new assembly by sanding down the inside of the hot wheel wheels so that the outer rim is only 1/8" wide. There is an innern hub that is still the origional width so the wheel won't wobble on the axel. I shaped the landing strut into a "U" shape that lays on the planes underecarrage so that I could get a good taping surface. Then angleed it out and down a bit before bending the end into a short axel and then bending over the last 1/8" to hold the wheel on. Note that the hub of the wheel faces out so that I can get greater clearence in the groove of my takeoff track.

The track is 1/2" thick with 1/8' depth cut away on the outside on both sides so that the front wheels ride outside of the rased center section. Then a grove is cut down the middle for the rear wheel to ride in. the track I have at this point is 7 feet long. With the wind and rain here I have only tried to launch in the house and I don't have quite enough runway yet. Putting the track on a card table the plane comes off too slow and drops but almost gets enough speed just before it hits the floor. A little more experimenting and i think I'll have it.