Yes, the methods are basically the same. The way you did it is just fine.
Adjusting the front left speaker, beginning with it set at "0" in the speaker setup menu, then setting it to 75dB on the meter by adjusting the master volume control, then leaving the master volume set, and setting the other speakers to match using the settings in the receiver's speaker menu, is fine also.
The only difference is, doing it the way you did, your "Reference" setting on the receiver's master volume is 0.0, and the speaker settings in your receiver's speaker setup menu are all at +something. If you do it the other way, your "Reference" setting on the receiver's master volume will be about +5, and the speaker settings in your receiver's speaker setup menu will have your fronts and center about "0," your left surround should be about -2.5, and your right surround should be about -2, and you sub should be about +1.5. If you're more comfortable with that, by all means do it that way.
You can always change the sub volume by using the volume control on the sub itself. If you feel that +1.5 is too high, turn the volume up a bit using the volume control on the subwoofer, and then lower the sub setting in the speaker setup menu until the meter reads 75dB again.
What matters most is that each speaker is matched to the others at 75dB, i.e. balanced. Either method will achieve that. Do it the way that makes you the most comfortable.
