Hey everyone, if you own an exo and want to lock up all three difs, here is a very easy and cheap way to do it. Go buy any of the lockers available like the hot racing or even use the "old iron cross" lockers that go inside the plastic housing. Then install it back into the rig and put it all back together. Next, slide the stock drive cups into the locker and find a spring that fits inside the drive cup and cut it to about a 15 -20mm length and install on both sides. Last thing to do is, grab your DVD's and install them pushing the spring against the drive cup keeping it pushed into the spool. I have done this on my exo on all three of them and have had very 100% success, zero fail rate to date. Harleys MIP idea is awesome and very strong just a lot on the pricey side.