I tried to find my original thread on my "church sub project" but it seems to have vanished.
I wanted to follow-up and show some pics of the finished project:
18" Peavey Lowrider in a 10ft3 ported (slot port) cabinet. 1000 watt amp. The box is very large when you're next to it - doesn't seem quite as big in the pics unless you remember the driver is 18" across.
It turned out VERY nice.