Hi,
The only reference I found on "barthmobile" to this catalog is from 2005. If you are doing some big work on your P30 chassis rig, you will want a copy. They are on ebay. You can also find a copy, page by page, over at gmpartswiki.com, but I find that hard to navigate. Sometimes there is nothing as effective as turning the pages and looking at the pictures.

If you search ebay for part numbers, you need something like this to tell you the GM part numbers.

And when you are asked, "have you read any good books lately", you can talk about control arms, wheel hubs, and why you need the part from the P42 series.

I have a picture of the cover, of an illustration, and of a parts list. The manual has hundreds of pages.

Happy Motoring,
Matt