I would not be influenced by the bonnet type as there are many early model Zeds running around with the bulge bonnets.
If you motor has the twin air intakes then it is an HR and the DE clutch kit will not fit.
Also the clutch bearing on the HR is a concentric slave type set up, so the bearings are different as well.
Helix do not do an oem replacement clutch for any of the Zeds as they only supply uprated clutches.
I stock oem replacement clutch kits for the DE and the HR and all good to go same/next day.
Drop me a pm if I can help you further.
Alex.