Intro
This has been a fairly popular modification over the years for a number reasons, with the main being the easy access to the engine bay. The factory cowl overhangs the engine cover and its required to be removed before other work can be done in the engine bay. The M3 cowl eliminates that process and also gives the engine bay a more open look, particularly nice for those with aftermarket intake manifolds or valve covers.
Parts List:
64316958817 Filter Housing Lower Left
64316958818 Filter Housing Lower Right
64316958815 Filter Housing Upper Left
64316958816 Filter Housing Upper Right
64319159606 Filter -> Aftermarket: Mann CUK 22 008-4
51718045623 Sealing (You can re-use your stock hood seal if its in good condition)
07143428231 Plastic Screws x6 (Assuming you don't keep your stock bolts, you'll use 10 of these total)
Optional Cable Guide, buy from schmiedmann.com:
12527838732 Cover for cable guide
12527838733 Cable guide
Installation
Start by removing the stock cowl, and then take the left(driver) portion of the cowl which is the longer side, and slide it onto the rubber seal next to the firewall. Use the factory bolt to secure this down as well as the rubber clips that hook into the sides.

Go ahead and install the right piece of the cowl. In the center, this piece sits on top of the other piece.

Next, break the three plastic tabs off the cowl to make room for the cable guide:

Go ahead and use three screws to fasten this cable guide to the cowl:

Now take the fatter wiring loom and stick it up into the larger of the two cable guide channels. This wire may be tight so be careful with how you handle it. If it doesn't reach you may have to undo the harness package on the bottom of the intake manifold in order to get room. Mark the loom on each side of the guide where the lines become exposed, and carefully cut the plastic shield off the loom:

Using black tape, re-tape over the exposed wires on the loom, make sure there are no holes so it is water tight:

Now take the smaller of the corrugated looms and stick it in the aft slot. It should be a perfect size and clip in. Right hand drive cars may have a larger loom and will need cut like the previous step. Next, take the newly taped loom and stick it in the next cable guide slot. Install the top of the cable guide and then hang the last wire on the exposed hooks.
Now install the new cabin filters and using the screws, install onto the cowl. If you have an alarm, the sensor should snap into the left side of one of the cabin filters.

You're done!
This has been a fairly popular modification over the years for a number reasons, with the main being the easy access to the engine bay. The factory cowl overhangs the engine cover and its required to be removed before other work can be done in the engine bay. The M3 cowl eliminates that process and also gives the engine bay a more open look, particularly nice for those with aftermarket intake manifolds or valve covers.
Parts List:
64316958817 Filter Housing Lower Left
64316958818 Filter Housing Lower Right
64316958815 Filter Housing Upper Left
64316958816 Filter Housing Upper Right
64319159606 Filter -> Aftermarket: Mann CUK 22 008-4
51718045623 Sealing (You can re-use your stock hood seal if its in good condition)
07143428231 Plastic Screws x6 (Assuming you don't keep your stock bolts, you'll use 10 of these total)
Optional Cable Guide, buy from schmiedmann.com:
12527838732 Cover for cable guide
12527838733 Cable guide
Installation
Start by removing the stock cowl, and then take the left(driver) portion of the cowl which is the longer side, and slide it onto the rubber seal next to the firewall. Use the factory bolt to secure this down as well as the rubber clips that hook into the sides.


Go ahead and install the right piece of the cowl. In the center, this piece sits on top of the other piece.

Next, break the three plastic tabs off the cowl to make room for the cable guide:


Go ahead and use three screws to fasten this cable guide to the cowl:

Now take the fatter wiring loom and stick it up into the larger of the two cable guide channels. This wire may be tight so be careful with how you handle it. If it doesn't reach you may have to undo the harness package on the bottom of the intake manifold in order to get room. Mark the loom on each side of the guide where the lines become exposed, and carefully cut the plastic shield off the loom:

Using black tape, re-tape over the exposed wires on the loom, make sure there are no holes so it is water tight:


Now take the smaller of the corrugated looms and stick it in the aft slot. It should be a perfect size and clip in. Right hand drive cars may have a larger loom and will need cut like the previous step. Next, take the newly taped loom and stick it in the next cable guide slot. Install the top of the cable guide and then hang the last wire on the exposed hooks.
Now install the new cabin filters and using the screws, install onto the cowl. If you have an alarm, the sensor should snap into the left side of one of the cabin filters.

You're done!