A64 overclocking isn't as simple as bumping up a front-side bus. While the guide is at least a year old, so is your processor, even if it's in the same family as AMD's best. That guide is completely relevant to your chip.
If you want to make sure you're at safe operating levels, simply don't adjust the voltages up from stock. I believe the CPU runs at 1.35V-1.4V stock, so just remember not to overvolt it past 1.4V if you want to be extra safe. Typically, the only safe way to operate at beyond stock voltage is to use cooling that's better than stock and to monitor core temperature to check how the cooling is holding up.