Be VERY careful at this stage.
Your leak could cause you thousands of $ worth of damage if you don't correctly identify it well.
Speaking from experience, indeed the base of my windshield leaked after replacement and the water ingress took out the electronics for the window/door lock ecu, the Bosch throttle pedal and a few others bits like the alarm inclination sensor.... (lhd car)
On the right hand side you have other electronics such as the suspension ecu, etc. so I'd advise AGAINST just using a hose with water in straight away. Firstly isolate the battery and remove all the expensive electronic ecu's from the area which would/could be damaged by water, before doing this so as to avoid water destroying them.
Before you even find the leak, firstly order some windshield sealant. Something like this; WINDSCREEN GLASS SEALANT BONDING ADHESIVE GLUE CAR | eBay
Then be prepared to spend several hours doing this. Its well worth the effort to do it right first time.
The other area on the 360/F430 which leaks (often) is the front black slam panel facia (under the hood/bonnet) where you access the wiper motor from, fluids, etc. You can order a replacement seal for this from Ferrari but tbh again the sealant/bonding glue will work just as well (if not better) than the original. This prevents water ingress into the front compartment area. Again a few hours here is worth the effort. In the front compartment, to do it properly, everything needs stripping back first, all trim removing, etc.