I guess I would steer clear of using anything else besides the fender hole.
Reasoning is mostly to where I live and the weather and debri. I know k+n can handle moisture but I don't think it would be to friendly to the stock panel paper filter. Adding the Y like you guy are doing might be a perfect water in let during rain or snow.
If the tubing intake could be dropped low enough where gravity would help keep the moisture out then that would be a plus.
I know 4.6 has the cylinder shaped filter.
The fender hole is the perfect spot to get away from all this.
Just some thoughts.
Peace!
