cam shaft taper angle

[Austin in the Shed]

You would be best to set up a camshaft in the lathe between centres, ,clock the taper up with the compound slide to get the angle,it's something like 3' 40" x 2 for included angle.
Then you are set to do the internal taper,check with Prussian blue to check it's right.It will of course "rock",(using camshaft as your gauge) if taper is incorrect.