Clean with naphtha and a soft cotton cloth, while wearing a carbon
filter mask, with a fan blowing the fumes away from you.  That won't
get everything off, but I believe will be the best way to get most of
it without damaging anything in the piano.

3M now makes a P-95 mask, which is a surgical-type mask impregnated
with carbon, available at Lowe's.  It won't stop all the fumes, but is
less bulky than the cartridge-type, and will help.

I believe that it is courteous when entering someone's house to
immediately ask where you can wash your hands.  Why would you want to
get whatever was on your steering wheel or from handling money on
anything?  This also should go for any workmen who enter, especially
someone touching something as delicate, fragile, and valuable as a
piano interior.  So don't be shy with your tuner: if he doesn't
volunteer to wash up first, tell him to!  You'll have protected your
property and taught him some good manners.

Gordon  Stelter