I drilled the discs on my old Honda Four by drawing down the pattern on a stiff bit of paper with a compass and dividers. Then stuck the paper to the disc and centre punched all the hole centres. Used the same bit of paper for both discs. Very happy with the result, however if you don't have a decent drill press then best to get someone else to do it.
Keep in mind that you will have to pay some one else (unless you gotta mate who can do it), and decent drill presses are not that expensive. So if you want to do it yourself it may be worth buying one. Upside to that is you will then have a decent drill press and they are a great thing to have in the workshop.