Boiled linseed oil.  I think it was on the vintagvw list that
I heard of this.  Use it like you would the Krown oil.  This
sort of oil or wax treatment is a British thing and perhaps why
 the Canadians use it.  We tossed out a lot of English ways along
with that tea. :-) I have only heard of this being used, I don't
know anything else about it.  I seem to recall the Brits had a
product called Waxoyl.
here is how to make your own http://list.miata.net/miata/1995-02/772.html

Of course, if someone has already mentioned boiled linseed oil on this list
then never mind.

Peace,
Dean Johnson
Williamson, NY
'90 Westy GL
'71 Super Beetle