If you think about it, the first version with the notch would be easiest to perform oil service on because the opening is right there. You wouldn’t have to remove anything. Whereas the second iteration, you actually have to remove a piece to access the drain plug. Am I missing something here?
Here are the three models. 64841400 Valid from Ass. Nr.20940, access to oilplug 64540500 Not for Spider - Valid till Ass. Nr.20939. access to oilplug 64684000 Valid for Spider - Valid till Ass. Nr.20939 - And for all CH(Swiss) cars, no access to oil plug View attachment 2972538 View attachment 2972539 View attachment 2972540
I know that early F355 rear bumpers have brackets molded into the bumper for attachment of the diffusers. See this thread: Rear diffuser mounting correctness
Small difference, the first item has some different air channel in the middle compared to the second one
Here’s the underside of mine - a US ‘99 Berlinetta. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login