As with most RVs built before the internet came about , a lot of information didn't become digital only existed in print .
GM , may have digitized some chassis info , but it'll probably come at a cost.
If you're after an appliance manual then with the manufacturer's name and a model number you'll probably find what you're after, online; because the same appliance could have been used into the digital age.
If you have specific questions then , I'm sure members here will be able to help .
The original Fleetwood company that built your unit declared bankruptcy in 2009 and was bought up , but I don't believe much , if any , of the original info is being handled by the new owner.