I understand the appeal & traditional aspect of using a featherbed, but since my main business is custom frame building, I think I can bring more to the party than a featherbed would offer.
An FB isn't exactly optimal for LSR stuff; its height, shortness and steep rake are much better suited to road-racing.
The chassis I'm thinking about would be more based on HD FXR architecture.
On the way home yesterday, I also picked up an early FXR tranny case - those familiar will know early ones had a removeable front mounting plate, which once discarded leaves a 4-bolt flange which will make mating to the Weslake rear flange a simple operation. A quick measurement indicates that FXR short primary centre-to-centre measurements can be used.
Serendipitously, Zodiac (dutch based HD parts distributors) currently have kicker only FXR Primo 3" beltdrives (with clutch) on offer at knockdown prices. So I'm grabbing one of those.
Its probably sensible to build it so that if I do grenade the Weslake irrepairably, a HD lump can be fitted without too much hassle.