Don't know if it helps Kev but the rear cylinder on mine always seems to run hotter than the front

. Thats with either the brown or white injectors (to be honest the white injectors made no difference at all) and a different ECU. The ventilation is I think is as good as the front even more so now without the airbox. Go figure eh.
Speak to Angry about it as well cos at Pembrey he had a temp sensor directly onto the rear cylinder.