Your tarp will work with a little modification. Just place your tarp on the top and mark where the antenna is then cut a small section out and reinforce it so it won't rip in the wind. Other wise a custom cover looks a lot better, you should be able to get one a round 1K and you don't have to worry about going over the top, it straps up under the top with a zipper down each side for easy entry.
Lee
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