Drumstyx, setting the timing with an Ohmmeter would not be my favourite. Back then mechanics at Honda dealers used to time the ignition by simply adjusting the breakerspoint gap as almost all 'off timing' originates here. So if your bike hasn't that many miles on it or was maintained before by a dealer, there's a good chance you don't have to adjust the plates.
Trying to set the timing without first verifying the breakerpoints gap, makes no sense.
You can adjust the breakerpoints gap by using feeler gauges (I'd choose 0,4mm). Personally I find a dwellmeter* very usefull. I always time the ignition by just readjusting the breakerpoints gap to the values I've noted long time ago. That is: if needed at all, because contrary to popular believe, timing does not often need to be adjusted as long as you have the OEM parts (often I did 20.000 kms or more and still didn't need to adjust). A quick check with the strobe has always proved me right. If you have twisted the plates however, you'll have to go the full route, I'm afraid, but once all is set correctly, you can further on adopt the method professional mechanics used to apply.
* Although an analogue dwell/tach meter would be my favourite, nowadays there are DMMs that offer Dwell/Tach for a very reasonable price, so if you need a (new) DMM, look for one that has these functions.