Hi. Yes, a 6mm hole will allow the tension adjustment screw to come through the housing like so:
I undid the screw 4 complete turns for a soft TPU and this printed OK (i.e. without stopping).
Instructions to remove the housing are on the wiki at The Toolhead Housing Assembly | Bambu Lab Wiki
BTW, I ran the max flow rate calibration test using OrcaSlicer (the one which builds a single width wall) and achieved a max flow rate of 17.5. I’ve seen suggestions to reduce this to 2 or 3 but high flow rates seem to print OK with the types of TPU I use. Still a bit stringy but manageable with a sharp scalpel.
I did try increasing the retraction but this didn’t have any positive effect.