I had tried out some new, generously padded soft leather seats at the Volvo dealership that I really liked, but just didn't have the extra $1,600 to buy them.

So, when a friend recently asked me if I had any need for a set of new old stock third row seats for a 2009 Honda Odyssey, I said yes and brought them home for a better look - wondering if I could possibly fit them into the Volvo.

The seats were comfortable – I mean really comfortable.  The back design provided excellent support all the way up to my head without putting me in an awkward seating position.  The gray cloth was extremely sturdy, the backs folded forward or reclined, they were 22" wide (Nationals are 20") and sported dual armrest.  The bottom cushions were much less harsh on my boney butt and the extra width made them feel more like furniture.  Some measuring and southern intuition told me that they just might work.
 

Original Volvo pneumatic National seat base with OEM tracks and adapter bars installed.

I took out the National seats, including the pneumatic base.  These suckers are heavy and the front loader on my old tractor was used as a crane for lifting.  Once out of the truck I removed the upper part of the National seat leaving only the base.

Honda Seat with factory mounting base.

I removed the entire floor mounting hardware, frame, and tracks from the Honda seats.  The challenge was discovering all the hidden fasteners and unlocking them without damaging the plastic trim.

Honda mounting base removed exposing the seat frame.

Lumbar air bags (3 position) in National seat - bag is removed....

On the driver's side, I removed the three-zone lumbar support air bag from inside the National seat and fitted it under the springs on the Honda seat.  Once secured, the air bags worked perfectly.

....... and installed between Honda seat back springs and foam padding.  Honda and National covers have zippers on bottom of back covers making inside access easy. Lumbar supports work great!

Pneumatic switches in aluminum side plate retain up-down and lumbar adjustments on driver's side seat.

The plastic surround on the Honda seats was too thick to hold the pneumatic switches from the steel side plate on the National seats.  I had to fabricate a thinner aluminum mounting plate for the switches that attached to the plastic surround.

Finished Project on passenger side.

View from passenger side.

Seats backs fold forward making it easier to put large items in the sleeper (like the mattress).  Headrest height and tilt are adjustable.

Passenger side - adjustable seat belt floor tether (red arrow) and up-down switch (yellow arrow). Round white and red thing is a magnetic base LED flasher stored on side of the seat base and has noting to do with the conversion.

View from driver's side.

Unfortunately, all of the bucket seats I salvaged for the Fiero based kit cars are too narrow for the HDT and do not have arm rests.  IMHO, the HDT needs a 20" to 22" seat.

What I am saying is just because a good seat may be dirty does not mean it can't be re-purposed. The pressure washer and sun will work wonders.  Just be careful with the pressure washer.  Too much pressure and too close can actually cut the upholstery fabric.