I am trying to figure out what headset I need. Below is a schematic of the head tube.

The fork I am using is 1.1/8" - 1.5" Tapered. Kinesis Range Fork - Carbon Fibre 700C Adventure Fork - Kinesis Bikes

I think I need one of the 3 headsets:
NO.42/48/ACB | FSA (fullspeedahead.com)
NO.42/ACB | FSA (fullspeedahead.com)
NO.42 ind | FSA (fullspeedahead.com)

If anyone could please point me in the write direction that would be great. Thanks.

Contact Cane Creek and ask them. They're very helpful and will give you the correct answer.

You will also need frame specs. If you have the year and model that should be enough to look up the specs.

NO. 42/48 is already out since the diameter of the top of your HT is 46mm. The differences between the last two has to do with the lower bearing for fitment on the 1.5" portion of the steerer. On NO.42 ACB, the bearing has a beveled edge of 45° whereas the lower bearing on NO.42 IND doesn't have that beveled edge. All you have to do is look inside the bottom of the HT where the lower bearing will be seated.

+1. The Cane Creek web site shows the entire range of types (external cup, zero stack and integrated) and diameters and should be a good guide.

+1. Or if this a custom or no-name frame try contacting the builders.

That head tube and fork probably requires an IS42/28.6 - ISS52/40 headset. IS42(mm) is the upper bearing outer diameter/28.6(mm) is the size of the top of the steerer tube. - IS52(mm) is the lower bearing outer diameter/40(mm) is the crown race seat diameter.

https://www.jensonusa.com/Cane-Creek...apered-Headset