Here are my line specs for the Sage Method Switch rods.

8 wt: Rio Outbound T-14 custom cut, 3 ft of head cut off to get to 476 grains
7 wt: Rio OBS 425 grains
6 wt: RIO OBS 375 grains

The Method isn't in production anymore so if you find a rod you like ask the fly shop or rod manufacturer what they recommend for OH casting. It's important you tell them it's for this purpose.

Good luck