I made curtains for my '61, my '67 and my '81.  None
were Westies--just passenger vans that I wanted to camp
in.

I used a plaid cotton and did not line them.  They worked
fine.

Since it wasn't a Westy, I had to make a way to attach
the curtains, so I stole a great idea from my brother
who did it first and made hooks and used elastic cord
in the curtain tubes.

It is all described at
http://jones.colorado.edu/VW/VWcurtains/VWCurtains.html
and there are pix of the fittings there, too:
http://jones.colorado.edu/VW/VWcurtains/
The text has the measurements for a Vanagon.  Somewhere
I probably have the measurements for Splitties!

Richard