Diff venting is definitely an issue. The two track days at Winton blew diff
oil all over the underside of the car with the stock vent setup. That's just a hose barb pressed into the back cover with a length of hose run up as high as possible.
The plan is to install a catch can breather setup.
Got any pics of yours? It'd good to get some ideas on how it fits in.
Cheers