Factory hardtops aren't strong enough to support that much weight, there's a high risk you'll crack your hardtop unless you provide additional support for the weight.
I have XK Cherokee roof racks installed on both my LJ and JKU hardtops and the rack is supported in the inside of the hardtop with brackets to the roll bars so no weight is borne by the fiberglass of the hardtop, I'd recommend you do something like that.