[gap]

Put water in the cutout box until the bottom of the washer nozzle touched it when the hood was closed. There needs to be 3/4" extra clearance for the nozzles.
The nozzles are 1.5" so there is only 3/4" clearance for the nozzle with the stock M3 filter covers. The plastic piece below the windshield has a metal frame member
behind it so mounting E90 washers there will be difficult. The cutouts I made are about 3/4" too deep so I will fill then Bondo and sand the indents to look more like the factory ones
on the front edge.
One of my washer nozzle retainer clips was broken off, don't know when it happened but think opening and closing the hood without clearance would eventually break the plastic parts.
Hood switch latch piece is about 1 1/2" X 1 1/2" and 1" thick. Trimmed to fit the hood frame.
Found these hose clamps at Grainger and used Zip Ties to attach to the cowl. 95* outside and with a fully warmed engine the exhaust size clip was at 170* so within the temp range.
My first filter cover attempt was pretty much a rush hack job and I will get back to it in a month or so.