The washers may rust unless you use stainless steel, why don't you use O-Rings , they are black and don't rust, Use Viton O-Rings they are very resistant to weather and salt, etc....Yeah. It was actually the wife's idea once I put it on. She's like that lower portion comes right off and you can just direct screw into the mount. And she said she thought it looked better without the added barrel. I agree I might place some washers to help offset the angle changes. I like it personally and the sound quality was perfect off the radio while I was still parked in garage.