John,
You might want to consider using a service bureau with a Versatec electrostatic
plotter. The smallest ones print 34" wide. A new model will print 52" wide I
think. They run in either 200dpi or 400 dpi modes in full color.
Prices range from $8-12 per square foot.
If you don't have a source I recommend The Association in Greensboro, NC. They
also have a 54" Laminator for laminating and/or mounting the print(s).
They can take your Illustrator file directly and output to any size you need.
They have printing specs on hand for almost all modular exhibit materials.
Tell them I sent you (I think I'm their biggest customer) (G).
— Bill
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