I don’t quite follow what you mean when you say “chorus insertion block” ... do you mean the Chorus Block or do you mean the Insertion A or B Block. There is no such thing as a “chorus insertion block”

Since you mention Dry/Wet balance, we will go ahead and assume you meant one of the two Insertion Blocks (A or B).
There are two steps to making this work.

1) Using the Dry/Wet setting inside the Effect Block, set the amount of Dry to Wet you wish to hear when the Wheel is down at minimum... recognizing that moving the Wheel Up will increase the amount of Effect(more Wet). This minimum setting does not have to completely Dry, set it to taste.

2) In the Control Set, one of your six setups will be:
Source = MW
Destination = either INS A or INS B (depending on which one is your Delay) - as you scroll through the Destination options you are looking for “Dry/Wet” balance. “Ef D/W”
Depth = Now with the MW all the way up, set the Depth to the positive (+) value that gives you the maximum Wet you desire. Again this maximum setting does not have to be completely Wet, set to taste