Hey Joe,<div></div><div>As long as the width of the A4 is the same as the A6, I don't see why you couldn't convert the A4 with A6 components. The most important part of the gearbox mounting is adding standoffs for mounting the gearbox down which you could find at Ace or most hard ware stores. Then you'd have to drill 4 holes in the A4 hulls axle slot so you can mount the A6's axle. If you get that done....everything else is just cake. You might have to use the Leo A6's sprocket though.

Edit: after examining the A4 manual.....it comes with standoffs. Not sure if you could make it work...but, it's a try. If not, then you might need to replace the 3 screws with long bolts than run all the way down and through the hull and bolt them in place. I think the biggest problem is finding the right height the 3 stand offs or spacers need to be.</div>