Woodman makes a headset to convert Headshok frames to 1 1/8" steerer standard. They list the cup OD as 49.5mm. So, the headtube ID either needs to be this size or have enough meat to ream to this size to use a Headshock fork.
Most integrated headsets fit a bore in the 41 to 45MM range (depending on specs). Yours appears to be roughly 42mm. Ain't gonna work.