yeah unless it involves alot of numbers or chemisty youll get more attention here.
chimera got his overflow comb laser cut up there somwhere, but you can also buy them ready made at the LFS.
the silicon used can be bought at the LFS sometimes as well alot of people suggest fosroc (sp), i havent found a supplier of that in hamilton so i have to use selleys stuff, (has a viniger smell and doesnt contain any anti fungal agents)
i didnt quite understand the first q.
you can paint the back (including silicon)