All-

First, I am not a painting conservator.  Paintings are not my specialty. Please speak to me as a layman.

I have four panels (3 are 3x5, 1 is 12 x 4) of acrylic painting on what appears to be pine 1x6 boards.  The panels are collectively a mural. They were on the wall in a bar for more than 75 years, and are of tremendous local significance.

The murals are covered in a combination of decaying varnish, cigarette smoke residue, and who knows what else.  I am hoping to clean some of this residue off the murals.

There is no flaking, paint loss, etc, that I can locate. It is as stable as it can be given its history.

Is there something I can do, as a museum professional but a paintings amateur, to clean these panels up a bit?  If not, understandable. Just wondering.

Please privately email so we don't overrun the list.