1) Improperly done crimps can set up a stress riser in the cables, possibly causing failure. If you don't have a high quality crimper, then it's probably better to use the AMA style wrapping. I use some 28g brass wire from some picture framing supplies I had, seems to work fine.

Here's one nice how-to:
http://www.clstunt.com/htdocs/dcforu...ID1/11840.html

An another:
http://www.clstunt.com/htdocs/dcforu...ID1/10973.html

2) Du-Bro makes little extender stacks, and it wouldn't be hard to make one since you have a mill. Do you have muffler requirements where you fly? If you do, then you may need at least a tongue muffler.

What airplane/engine/muffler are you thinking about? It might be all right for balance, or the stock muffler might be lightened a bit (the mill, again).

Kelvin