I used 2 rear SKS/Blumels Sovereign, {brand merger) mudguards (custom biplane fork , drilled & tapped under lower plate)

+DIY mudflaps..


I thought your 'daruma' thing filled the bottom of the fork steerer tube with a nut, to directly screw the mudguard under your fork crown..

which I accomplished with a flat lower plate drilled on the ends for the fork blades to pass thru..
upper plate, the steerer passes thru.

both penetrations and butt joints then Tig welded in place... FWIW.





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