Help Identifying 4z400

I need help identifying a kz400 i just bought, it is supposed to be a 75 as per the title yet I am having trouble identifying model as per kz400.com

Engine # K4E 036658
Frame# K4-035183

Any help would be appreciated.

BTW front disc brake rear drum

According to the KZ400.com website documentation the engine numbers for the 1975 KZ400-D2 began with K4E 013844 and the frame numbers began with K4-013800. The engine numbers for the 1976 KZ400-D3 began with K4E 050601 and the frame numbers began with K4-044601. (see image below)

Your engine number is K4E 036658 and your frame number is K4-035183. Since your numbers are higher than the 1975 KZ400-D2 starting numbers and lower that the 1976 KZ400-D3 starting numbers your bike falls into the 1975 KZ400-D2 number range and is therefore a 1975 KZ400-D2. Ed

Thank You, any idea where I can get a carb and gasket kit for this particular model? Will later model kits work? Everything I find looks to be 76 on.

I don't know about a kit, but Kawasaki.com still lists the carb bowl O-ring and float valve O-ring as"Active" parts. Ed