Dual power-supplies is popular in mining rigs, if one fails you still have half your hashing power. Also buying two less wattage PSUs is normally cheaper than buying one one huge one, so you get better value per $.
So long as you have the necessary connectors off one PSU, then that is the route you should be taking. You would be best sharing your specs with us though in case you've missed something obvious.
7th gen celeron
4gb ddr4 2400mhz
120gb ssd
6X gtx 1060 3gb
"Whatever Powersupply I get"
B250 btc mobo (I think its the biostar one)
DIY rig case/mount/rack
Standard GPU risers which I already have
Dual power-supplies is popular in mining rigs, if one fails you still have half your hashing power. Also buying two less wattage PSUs is normally cheaper than buying one one huge one, so you get better value per $.