[The Radium King]

there are pics of this floating around. done to the early 996 rsr cars I believe. block the standard airflow path out the back of the rad and under the car and use a holesaw to drill holes from the back of the rad ducts into the wheel wells. I don't think the purpose is to improve cooling, I think it is to reduce the amount of air blowing down and trying to lift the nose at speed.

the next step would be to vent the fenders at the top just forward of the wheel centreline. aerodynamic analysis shows that this is the point of highest pressure, which can be converted to downforce if allowed to flow upwards out of the fender.

I've read that things run cooler if you remove the underbody panel just in front of the engine. otherwise, consider an oil cooler: ln oil filter adaptor - canton sandwich plate - two an hoses - canton thermostatic valve - two an hoses - setrab cooler mounted in the rear wheel well.