Jack,
I'm going to be of very limited help as I have the same year as you but on a different chassis.
On mine the driver seat is fused by one of the push-button black resetable 12v fuses, not the blade type auto fuses.
Have you checked your 12v panels? Looks like in the brochure there is a bank of them where your radios and rechargable vacuum is stored.
Also perhaps (as in mine) you've got a panel of the push-button 12v fuses in one of the bays?
Again, sorry may not be much help with a different chassis, but perhaps Winnie did the same general wiring on yours.
Just some ideas...