RIGHT!
On my amp at least, unity gain isn't at 12 oclock, but it also doesn't move around as the levels change, just the return control is quite sensitive.
in series my starting levels on there are at 10 on the send and then around 7 on the return, and that will provide you with a similar level the raw channel level. Then you can work from there balancing the send and return as you wish.
the drive pedal also work in parallel mode as a supplement to the raw Randall tone which is wicked, although the levels need a mess around to get the right mix! Got the creamyness and mid-boost of the Hot Tubes running in parallel with the pure randall tone and which makes a nice rolled off lead tone with LOADs of presence. I'd go through the settings of that but you'd have to tweak it to get the hot tubes just right and that takes fookin ages, that pedal is incredibly difficult to work with for any useable sound!