At the risk of sounding like a broken record,  look in "The Guild
Handbook," pp. 154, 421-22, listed under "cel painting" in the Index.  In
the Bibliography, under "Illustrating Medical Subjects," p. 556, is a
reference to an article by Steve Harrison on "Cel Vinyls: Materials and
Methods" from the J. of Biocommunication, Vol. 10, no.4, Dec. 1983.  Maybe
you can obtain a copy of this article or original issue from the AMI
(phone: 404-350-7900) or a friendly long-time medical illustrator.  But I
have the issue and will photocopy the article and mail/fax it to you,
Lynette.  Can't promise to send this to everyone on the listserv!

Elaine

Elaine R.S. Hodges      [log in to unmask]
85253 Ridgetop Drive
Eugene, OR  97405-9535  Phone: 541-684-0484, Fax: 541-684-9662
        USA