In the end i did both, reduced the diameter and added a cutout. It's a bit rough looking but there are no gaps bigger than the actual holes anyway. Clearance from the bottom is 24mm in the centre and 11mm an inch in from the outside
edge. I'll pick up a smaller barb and cut some heat tolerant...
I was originally going to make a manifold but i found a really cheap false bottom. I'm going to try and cut it to fit around the boss and just see how it goes.
I have a 35 litre cooler with a 30cm false bottom (and a 1/2" ball valve tap) i was hoping to convert to a cheap mash tun. Only problem is the cooler has an inconvenient inwards ridge where the tap sits which prevents the false bottom from sitting on the base. I figure my options are either...
At risk of heading off topic; can i harvest and wash yeast through the dump port of a conical just before dry hopping? Or would this just give me more trub than yeast and/or leave my current batch low on active yeast for the final couple of gravity points?