Not sure what you mean by 'decals'.  Assuming we are talking about the 1976 Gottlieb SURFER, is it the cabinet art work you require?  These were painted directly onto the cabinets back in those days.  If you contact Gavin (Retropin) of Flipper Rescue http://www.flipperescue.com/ he is the licensed Aussie manufacturer / distributor of Gottlieb stencils...

As far as the trouble shooting goes, have a read of http://users.esc.net.au/~boots/Pinball_Guides/default.html

What I don't know about EM pinnies could fill a warehouse