Take some tools, spare protectors, and cable ties just incase you are asked to fettle something minor to avoid a fail. Work the brakes as best you can on the way to the centre to bed them in, as they will be tested. No idea about the IoM test, but if you haven't already submitted the certificate of newness, build photos, copies of invoices etc. it may be sensible to take these along as well. Best of luck on Friday.