Most of the following have already been done in Dewsbury
Flat Cap Friday - a celebration of the Yorkshire dialect. Turn the occasional get together into a major attraction.
+ 40s/50s dance - done before in Dewsbury
+ persuade the Grand Northern Ukelele Festival to spill over from Huddersfield
+ classic car show - already held regularly in Dewsbury
Bring them all together in a Vintage Dewsbury Celebration weekend festival.