Want to build my first doubler. Looking for tech articles/expeince on doublers to mate to AX15. What T-Cases to start with, etc.:D

You'll pretty much have to go through a NP231. So NP231/231 231/D300 etc

There are other ways, but that would be the easiest.

http://www.pirate4x4.com/forum/showthread.php?t=399755

thats the route I took. Nice kit. Still in the process of finishing things up, as I did this as well as 1 ton axles, wheelbase stretch, and fuel tank relocation at the same time.

I have the Mad Rooster doubler kit on my TJ with the 231 mated to another 231 with Tera Low. Only made one run on this setup but I loved it. I also did a Wheelbase stretch and gas tank relocation at the same time.

http://www.pirate4x4.com/forum/showthread.php?t=432139

I like the D300, the NP231 strength even with a SYE kit won't hold up to the abuse of rock crawling.
When I read about the Mad Rooster kit, I had to buy IT !!
It eliminates the weak parts of the NP231 using just the reduction and does a GREAT job of connecting both cases up to make a 7.1264 to 1 at a price that is reasonable, also EASY to do !!

If you haven't seen my post on this site.. take a look above.
Good Luck with your build.
David B.

I have the Mad Rooster doubler kit on my TJ with the 231 mated to another 231 with Tera Low. Only made one run on this setup but I loved it.
That's good to hear,that's the route I'm gonna go.