I put a linear pot in mine and wired it to a TRS jack. Some units (and people) don't mind the log taper on a volume pedal, some do.I use Ernie Ball pedal, have no idea what would need do be "converted"..? Mine works fine on my 11R and my G3 right out of the box..
Mission Engineering SP-1 here. I have three of them. They've held up to the gigging.