Here's another idea--that I stole from someone else on the list.

Replace the drain hose with some Home Depot (or equiv) hose and
then remove the false bottom in the cabinet to get more room.

Pictures at:
http://jones.colorado.edu/VW/SinkDrain

The reinforcement under the van, with some RTV and a big washer
was for...I forget.  Maybe something was cracking.  Oh, now I
remember.  It was the original floor fitting and the flanges
for the screws were cracking.

My P-trap was fine, but the flex hose was cracking and starting
to leak, which is why I did this.  It was a GoWesty replacement
from many years ago but the picture on their web looks the same.

Don't ask what the box on the cabinet wall is.  It is the control
box for my Vitrifrigo....

Richard