Cool. U(sincerely - I do remember these moments...)
Anyway, you could have spared some of thwe work (deleting parts of the circles) by using teh arc tool instead.
Moreover, you can always enter values into what's now called the "Measurement box" (in older tutorials you will find reference to a certain "VCB" for this). So in a case of an angular input, just type the angle and hit Enter.
Also, to make it easier, scroll down to where uit says about "Radial arrays" on this page.
(and when you are at it, also examine Linear arrays here)