Howdy Phil! Will I be seeing you at WKRP again this year?
I think that you'll find the most important parts & accessories to carry will be very similar to your scooter biz.
of course, the "wear items" are important - cables, oil filters, bulbs, etc... As for Repairs... only time will tell with the UCE's.. for older models perhaps head gaskets and that sprag clutch thing, a nice assortment of sprockets.. ignition bits.. I haven't had a single "repair" needed on my '07 iron yet, so I don't know what to say.
Accessories... seats, windshields, grips, tail lights, luggage, chrome bits. 7" headlight conversions. exhausts.
My dealer is AWESOME. My only wish is that he wasn't 100 miles away.
I know that if you bring the same dedication to Enfield as you do your scooter biz, you'll be great at them.
cheers,