I have researched changing the .12 engine to non pull start and the information is conflicting. Some say you just need motor mounts, backplate, and a flywheel. Others talk about having to trim the crankshaft.
I got the NTC3 to get my feet wet in nitro (got a great deal from a RCTech member).
If you could search way back in your memory banks and help me out with some information, I would be grateful.

The motor mount/backplate/flywheel part is because non PS motors need to sit a pinch lower so the flywheel can contact the starter box wheel through that slot (thats what its for!!)
The ones that say you need to cut the crank; there are two types of cranks. SG and standard. Disassembled they are easily told apart. SG is longer, smoother, and only has about 1/4" of thread on it. Threaded cranks are noticeably shorter, and the entire length is threaded. For non PS applications, you will want th SG shaft. Hopefully this helps

That is exactly what I needed to know. Thanks!

If you plan to remove the pull starter from the engine and put a non-pull backplate on (I recommend this as pull starts are often culprits in air leaks), you will likely have to cut the tab off of the back of the crank that the pull start engages.
While I agree with most of what Giant655 said, a threaded crank can be used for non-pull start engines as well.

Thanks NutDriver. I am going to take off the pull start and put the backplate on.