Jonathan, great news! And a great radio! Glad to hear you are supporting your local biz too. As far as the antenna goes, I agree with asteffes - you could always mount it on the rear and get it tested. Likely that same HAM shop will able to do it for you. There is a device called a "bird meter" that the shop may have, which would be great to test that location for you. If it doesn't work well, then the next "easiest" placement would be the hood channel on the front, if the gap between hood and fender is enough for a bracket to slip through. You might have to make a custom bracket for the 40, but that would keep you from having to drill a hole in the roof and the hood area should provide a decent launching pad for your transmissions. An NMO mount on the roof would probably yield the best performance of any choice. That big roof on the 40 would be excellent for that.