I've had mine off before and don't recall seeing any shims. The top's front rubber on mine is shot so it does leak when driving in a heavy rain. I did notice that if the anti-rattlers are out there is a better seal. I've got SoffSeal's E-body convertible top kit, just haven't opened it or installed any of the pieces yet. It's "CH3400" and does come with the that seal at the chrome piece you're talking about. I'd get a new seal first then take wiging19's advice and tighten the latches if it still leaks. Also, if the mounting screws are too tight it can dimple the chrome and maybe cause a leak.