I recently had to remove my supercharger and flushed the coolant using the vacuum refill method after I re-installed it to make sure there weren't any bubbles in the system and am curious about the process that you used. I'm asking because I paid for a subscription to alldata DIY for another reason and checked on the coolant flush process which showed one step that I wasn't aware of before I did the flush. It's opening and closing two air bleeder valves. I'm going to flush the coolant again this weekend following these instructions since it's really easy with the vacuum refill tool but still wanted to check with all of you to see if any of you did this.
Side note, in case any of you ever need to do this, I bought this fill adapter from prospeed (link) and it worked perfectly with this refill system tool (link).