The tung oil has been working well for me on my 380L/PZ and now on the 330W, although the wood seems fine on the new 330W so really haven't given it much of rubdown yet. I believe there is something about the care of the Walnut finish on the brochure that comes with the guitar. You can also download it here:
http://www.rickenbacker.com/pdfs/manual.pdf
It say:
Oil Finish Maintenance
Beyond routine cleaning, the best
way to maintain a hand rubbed oil
finish (as seen on Rickenbacker
Models 650D, 650S, and some
older models), is with Tung oil and
a 3M Scotch-Brite™ Ultra Fine
Hand Pad (#7448.)
Using small amounts of oil at a
time, wipe down the instrument
until there is a relatively uniform
coating on the surface of the guitar.
Going with the wood grain, use the
Scotch-Brite™ pad to lightly sand
the surface until it begins to take
on its original silky smooth feel.
Before setting the instrument aside
to dry, use a clean, lint free cloth to
wipe down any excess oil or grit.
Allow 8 – 12 hours for proper
drying.
This procedure can also be per-
formed using ultra fine, light or gray
colored sandpaper. A minimum
grade of 1200 should be used to
avoid damaging the surface of the
wood. It is also important to avoid
black sandpaper, as the residue is
likely to stain the instrument as the
oil sets in.
Use of steel wool is not recom-
mended as the ferrous residue
can cling to pickups. Particles of
this residue can also become
suspended in the finish and rust
over time
But I still use nylons. (will have to explore having the girl in the nylons idea further!!

)
Have fun!!
