Here goes.....
Unbolt dickie seats, carve a chunk out of the panel underneath, on the side with the fuel filler "persuade" it into place. No panel beating needed on the other side.
Stick a big bit of foam over it.
Use long bolts in the uper mounts.
Spend a long time using the dickie seat as a template. Cut out the front panel. Add vertical MDF strips to enable it to bolt to the top mounts. Use angle iron to bolt to the bottom brackets. After days of fiddling/swearing/sanding/swearing/screwing/swearing cover the whole lot in speaker box fabric and chuck some cable in.
Attach the cover to the bottom mounts.
Fold the cover into place. Put your hand through the hole and bolt it up. Screw the sub in.
Hey presto....
The bumf with the subs said they could be enclosed, ported or open - hence it's only a cover.
Grand Total.
Fabric £25 @ Halfords
Mutant 12" Subs £26 @ Ebay
Cable £20 @ Ebay (
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=310162021514)