Hi XR8beast , glad to see another ATM on the forum.
The reward that you will get from doing it your self will be very satisfying .
I have ground 3 mirrors many years ago from 4"- 8"and my only advise for your first and as it is an 8" is to make it a longish focal ratio of at least f6 or more.
Even an f8 make a wonderful planetary scope and is still good for visual deep sky.
The slower light cone is also easier on cheaper eyepieces, so you don't have to go and get expensive ones starting out.
It is a lot easier to figure an f6 than say an f4.5 or 5 especially for your first.
Also if it is going to be a Dob , you will want the eyepiece at a reasonable height .
i have included a link to a very popular program for ray tracing a Newtonian's optics.
Read the Help files , mainly "notes on design".
http://home.att.net/~dale.keller/atm...t/newtsoft.htm
Happy grinding Mark