Rob,
There are lots of places to put subwoofers, depending where you want to
sacrifice space and how much you want to cut up your van.   You have the
same year Westy I have so I feel your pain about not wanting to give up
space.   I ended up putting mine under the rear seat and it has worked out
well.   Anywhere you put it will be a sacrifice in some way, so I guess it
just depends on how you use your space and the quality of sound you want.
You can see my stereo system at this link, the subwoofer is on the next
page.
http://home.earthlink.net/~matsuwesty/page48.html
Hope this helps.
Matt

Subject: Vanagon Subwoofer option(s)

Hello-

I saw Larry Chase's nice summary of subwoofer options in the archives,
but I don't see the results of what he chose. My new-to-me Vanagon has
a decentish head unit and decentish speakers, but it has a hard time
overcoming highway noise. I believe adding a subwoofer and amp will
take the load off of the main speakers and allow a little more clear volume.

I am reluctant to give up space anywhere to speakers... but I think I
have an answer. The speaker cabinet linked below will fit behind the
drivers seat. My measurements may reflect the fact that I am only 5'4"
so might have the seat a little more forward than is normal. If the
cabinet is attached with velcro to the carpet, and slack is left in the
wires for moving, it seems an ideal way to use that awkward space.

http://tinyurl.com/29knm
or
http://www.crutchfield.com/cgi-bin/S-wq6kujUNKVr/ProdView.asp?s=0&c=10&g=842
&I=044T3508SE&o=m&a=1&cc=01&avf=Y

Are there problems with a seat in this space I am overlooking? I
measured twice and tried hard to imagine the box there, it seems better
to claim that space than any of the cabinet or floor space anywhere
else. I would like a heater behind the passenger seat, so that is out.
I am undecided about the space between the driver's and passenger seats,
but I really doubt I will want speakers there.

The space under the backseat is another good spot (from the speaker's
point of view) but that seems too precious for storage.

The best thing I saw listed in Larry's survey was to do something at the
bottom of the hanging closet. My concerns there are that the closet
itself will block sound and need to be vented, and that items stored in
the closet (blankets, sleeping bags etc) would make it an ineffective space.

I would love any advice or shared experience.

Thanks,

rob campbell,
seattle
87 westy
http://www.dokodemo.org/van.html