They were all built on the P30 chassis (sometimes referred to as a P37), but consider it a P30. They came in seven flavours of varying wheelbase lengths. All this is set out in detail in the Chevrolet Motorhome Chassis guide and alignment guide. You can download a copy from Airstream.com or there is a better searching copy floating around somewhere in cyberspace. Also worth looking at the excellent P30 alignment guide on Omeys-Peeformance.com, also free. Both essential for people who want to properly maintain these rigs.
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