I have used a Dremel tool to buff down the Olympic rivets, it works very well, is much less expensive that a shaver, and you can use it for other projects than just rivets. A good, multi-speed Dremel tool is around $100, and comes with a variety of attachments.
Our roof had a hole corroded in it where the tv antenna is, I covered the area with a fresh aluminum sheet, vulkemed the seams, potted the rivets with Vulkem, and installed a new antenna in place. Anybody that's standing on the roof can see it, but if they don't like the view, they can look somewhere else.
