I did it. I got tired of those useless vent holes on the deck of my EX-16 and decided to do something about it. I was pretty frustrated with the vacuum system and after about 2 hours of use, removed it. Small pieces kept getting hung up. I thought for a while about how I could fill in those holes and finally came up with using 5 minute, 2 part epoxy. I taped off the lower section to hold it in place and mixed up a batch and applied a layer slightly thicker into and over the holes. Since it dries to a hard rubber like consistency, I was able to use a straight razor to shave off the excess. Applied a 2nd coat because it tends to well a little in the holes and trim again. What a difference! It is a whole lot smoother!
In a previous posting, I mentioned that I had swapped the lower blade tightening screw from the right to left side. That also made a difference in that I can use both hands tightening the blade and tensioning. I did have to reposition the motor to square up the blade. Looking for my next tweak.