2 Tekin questions, Both about BEC's

[team3six]

#1. OK, so I have a RC4WD copperhead crawler. I have set it up with 2 servo's. One for the steering and One for the Dig. Talking to Ty from Tekin at the Comp this weekend, I was told that I would need to place an External BEC running the Tekin FX-R w/ 55t brushed motor because the internal BEC only can handle 3A.
So today I purchased a Common Sense BEC. (This one in the link.) http://www.commonsenserc.com/product...roducts_id=323
The instructions http://www.commonsenserc.com/XBEC_Instructions_flat.pdf
basically show use with a lipo and it is rated for 3S and higher or 7 to 28 cells. But the diagram and instructions are for Lipo. Im pretty on top of things when it comes to figuring out electronices. But since it is obviously required I run a BEC. My set up will have an 8 cell saddle pack 1500 NiMH Sub C battery pack. can I still use this BEC or do I need to purchase something else.

#2. the second set up is my Evolution. I removed the Novak system and will be replacing it with the appropriate RX8 system. the issue is that this is a 12 to 14 lb truck, 2WD, and has duel servos for steering in the front. Suicideniel knows this truck pretty well as we have talked about it. Now Niel suggested I should go with a pertiular motor out of the groups. But i am wondering what tekin suggests for this truuck and would this common sense BEC also work in this or will i not have the need for it. It will be running on (2) SMC 2S 5000mAh 25C Lipo's. The servos are (2) hitec HS645MG's. Pics of the truck is below.