RE: prop shaft help
Nightshadow.
This may help in the general installation. Of course all the measurements may be different for your actual hull & motor placement. But it gives you the general Idea.
[link]http://www.finedesignrc.com/pipshovelsetup.asp[/link]
Google is your best friend. Click on any of these pics & you can read the article that is associated with it for more info.
[link]https://www.google.com.au/search?q=R/C+Hydro+stuffing+tube+%26+shaft+installation&bav=on.2,or.r_qf.&biw=1663&bih=793&um=1&ie=UTF-8&hl=en&tbm=isch&source=og&sa=N&tab=wi&ei=oI_DUd3PCoaAiQft9YBA#imgdii=_[/link]
Cheers.
Paul.