on my bully i had the same issue
it did fit in the end, but it was really tight and fiddly
tbh it was such a pain in the arse to set up. and the brake's woeful performance didn't really warrant the fannyarsing around it too setting it up either.
post a pic. it may be that you need to run a side pull
either brake choice aint gonna be giving you massive skids
unless you count the ones in your grippers as you head towards a busy road with the back brake on full chat, but not slowing you down