[settingsteel]

Seems your well set on your project, congrats!

The t-lam fox mentions is not too complicated to add and quite a few DIY'ers go this route, IMHO unless your minimizing your wood specs (which you are not) I don't think you really need it, but then again it doesn't hurt either (I'm in the process of making a gun with absolute minimal dimensions which has carbon fiber b/t the lams and the actual "T" as well), the same holds for a pored track vs an all wood track (which I would recommend you implement in your gun).

The grip looks great, your trig mech I can't exactly decipher, but Steve Vero (poseiden) makes a great trig/auto release for $75.

Shafts are easy to fabricate in SS, the problem arises when you go into S. springsteel, its the rods that are difficult to secure, Ray Odor-http://www.spearfishing.cc/WebPage1.htm makes them with pins and a doghouse for a good price and quality.

good luck on your project!!!