Yes, you can plug it straight into the power amp as it has high output voltage swing.
I never tried to separate the outputs, but it should work. The first stage will be loaded more with both outputs plugged, but don’t know whether it will make it sound different or not. It’s worth trying if you need two outputs…in case it sounds different in a bad way, maybe a solid state buffer (IRF820 or something) at the end of clean channel would help.

Cheers

Using the Marshall Tonestack was brilliant.

Can your “Tube Reactor Pre Amp” be plugged directly into a power amp? Or, does it work better in front of a standard guitar amp?

Secondly, is it possible forego the channel-swithing and keep both ‘channels’ on at the same time? …like a multi-amp set-up or a “Voodoo Labs Sparkle Drive”?

Keep up the good work.

Rob