Need suggestions for clean butt splice for electrical wires.

I'm working on the firewall forward for my homebuilt.

I need to extend various wires to make it to their respective destinations.
(14 to 26 gauge wires.)

Any way to have a nice clean butt joint? I don't like the crimp butt joints
or twisting the wires together with the accompanying monster bulge.

What have y'all used for a central ground or central power point? I'm building
a composite so I can't use the airframe as a convenient ground.

Suggestions and/or pictures are appreciated.

Thanks

--
Bart D. Hull

Tempe, Arizona

Check http://www.inficad.com/~bdhull/engine.html
for my Subaru Engine Conversion
Check http://www.inficad.com/~bdhull/fuselage.html
for Tango II I'm building.