Quite easy to do this…

I would go with BUS just for having the volume proportion.

If you want to send channels with independent volume control then you should go with SENDS (i would choose the PRE-Fader one)

But, since BUS are conceived for recording…then sample with BUS…

Even if, on my digital desk, i use AUX send PRE fader to feed the OT. But this my desk is digital and there’s no difference between the two signal path.

About OT, just b sure you dont hit red leds too long…remember you always have a lot of post-amplification to raise the level of your sampled audio.

So, just check levels using DIR or THRU then proceed with sampling if everything is fine or reduce or raise a bit the input GAIN…that’s it

Easy pie