To get the best sound & avoid mounting depth problems, locate the sub as far away away from the port opening...otherwise, like you said, just add a spacer...
yea, you'd be ok, as long as it's tuned @34hz....
at the bottom of the carstereo page , you could calculate port length...
34.85hz seems ok, although it's leaning more towards 35hz, especially if you're gonna brace the box & add corner fills...
make your port longer til it hits 34hz or make your port area bigger for 36hz...
146.25 is ok, 146.03 is just your minimum @34hz...
not sure what the negative number could mean...???
just keep playing with it, til it all falls into place...
since you're not doing a round or square port, you can ignore the diameter & length for a square vent...
right, you would have to come up with at least 137.44sq.in.(@32hz) of port area to avoid port noise....
port area is still way too small, use this site to help you figure out your minimum port area for that sub:
http://www.carstereo.com/help/Articles.cfm?id=31
On second thought, there is no "best" set up, every one has different taste, there are thousands of options for you, the best set up is what works for you...
I remember back in seventh grade, i had a home theater system and didn't know much about impedance loads and hooked up 4 10's(all parallel) and the system blew after a few seconds...