Thanks for your prompt reply stringscope,
You dont need the software... go to
http://stellafane.org/tm/newt-web/newt-web.html
Under the file tab, at the bottom of the page you can load a newt file. Unzip the attached file and move the newt file to your desktop. Then go to "Open Newt file" and browse the desktop for the file.
I. I have not calculated anything so far as i dont have any of the components in my hand...although i could estimate and take guesses off other sites...will do that now...
2. ID is 18"
3. Tools and capacity...sweet bugger all. Ive enlisted the help of my mate who has shop fitting skills. He cuts the wood. I have "the book" lol.
5. Budget is ~2500. I know theyre not cheap, nor are the astrosystems alternatives... its a cost to quality to difficultly in making ratio....
6. 400mm constraint is based on the space of my boot. Back seat wouldnt be accessible with any sort of width purely based on the non 90 degree door.