Mach subwoofer replacement

Just bought a '98 Mountaineer, it's my first car in fact...

I soon found out that the subwoofer in the Mach premium sound system is blown. As far as I know, it's a 8" JBL. It was $260+ to have it fixed through the dealership, so I have decided to go aftermarket. I purchased a new amp, which I should have no problems wiring up. I also bought a 10" shallowmount subwoofer to be mounted in place of the old JBL speaker, behind the factory panel.

What I was wondering is, do I need to fabricate a new speaker box for behind the panel? Has anyone done this and have any ideas? To save room, I was thinking that I would cut a hole to put the sub in, and mount some sort of box behind the panel.

Any ideas? Anything would be appreciated!
Thanks! :

I was looking at these for my '97

http://www.crutchfield.com/g_182750/Vehicle-specific-Enclosures.html?tp=129

The stock enclosure works fine, and fits perfectly obviously...

A JL audio 8W1v2-4 fits in the stock location perfectly and sounds great with an aftermarket amp...

What a sucky coincidence.....I reply to this post this morning and this afternoon I notice a funny sound in the Ex. Yup you guessed it the JBL sub went poof. Joe what did you have to do to add the aftermarket amp to the stock system?

For a cheap fix, we used this:

http://www.amazon.com/Boss-CX8-Subw...EW/ref=sr_1_14?ie=UTF8&qid=1287963658&sr=8-14

The mounting pattern is just slightly smaller, so we had to drill new holes in the plastic box and oval=out the grill/foam piece. Otherwise it seems to work great and is shallow enough to fit.

AM.

hey nd4spd- sorry I didn't see your question... If you haven't fixed it yet, here is my writeup: CLICK ME

I replaced it with a JL Audio 8w1V2-4 sub from carstereoonline.com which fit perfectly, I re-tapped new screw holes, but just drove them in with my cordless screwdriver, no fitment issues at all.

I bought a new amp to drive it, the JL sub, and sub wiring install kit for $160 delivered.