Thought I would resurrect this thread since we have become owners of a 1975 Excella 500.
The owner's manual is original, brown padded hardcover.
Service manual looks like it is a photocopy -- comb binding I've removed to make a photocopy for safe-keeping -- or maybe I should be plasticoating it???
Copyright 1975, cover says "1975 Excella Service Manual." Exterior drawings do not match our unit!?
A note printed inside owner's manual says: Service information for the 1975 Excella will be included in the 1976 Airstream Service Manual, available December 1975. (Thought this info might help someone.) Not familiar enough with unit or manual yet to know if it's advisable to get paper copy of 1976 manual.
On the other hand, if anyone has put either the 1975 or 1976 service manual on CD, could I buy a copy? (I don't think I'll be scanning this one in, because I haven't been able to get scanner to cooperate yet!)
If anyone needs copy of a given section (subject), let me know. It does include info on trailers of other lengths and layouts. I did notice that one page was not well copied (blank in the middle). Haven't examined every page.