Using a front axle housing on your rear axle
 

First of all this was not originaly my idea, but I failed to find a decent write up to follow along to when I wanted to do this. Hopefully this makes it a little clearer.

If you look in the manual for the front axle directions, when you get the the final gear(step 7), put it in the opposite way that the manual suggests. The 110mm shaft should go into the nonrecessed side and the 117mm shaft should go into the recessed side.

Drill out your Final Gear,NOT the recessed side, to 1/4" about 1mm deep. I had to use a 13/64" bit first to make the drilling go easier using a hand drill. You really need to test fit(i.e. putting the whole axle together with the bearing and lockout) this with the 110mm axle shaft as you drill to make sure you don't drill too deep.

I also added a Traxxas bushing(TRA3775) on the 117mm shaft at the locker, it may be better to shim at the lockout to get more engagement in the locker... to me it felt right to shim at the locker.



I did this mod because I thought it would save weight in the rear and also make the axle more reliable.

I was weighing as I went and it appeared to be saving me about 2.8g in plastic weight(this is with the brass inserts installed in the front axle and no inserts installed in the rear axle housing). I also used the short titanium gear shaft which saved 4.3g over the stock long one. There should also be weight savings in the smaller amount of hardware used on the front axle than the rear... I did not weigh this though.

Hope this helps at least one person out there "thumbsup".

Um. Your is a lot different than mine. My shafts and final gear are flipped. I also drilled out the Non-recessed side. I don't think that really makes a difference though? The big difference i see is a put as much shims as i could behind the bearing in the lockout to get the most engagement at the locker as possible. I doesn't look like you have much at the locker. I shimmed mine so the hex barely clears the lockout.

Edited first post... based on input from stubs179... Sometimes I overcomplicate things :)