They vary on how far the front lip hangs over... it depends ultimately on where abouts the bulkhead was positioned, thus the angle of the screen (against the doors) and the door slam gap.
Whenever i've fitted them (the roof, be it a full roof or a truck cab), i firstly make sure that the screen is as the same angle as the door tops (easy if you have the "fixed" hinge as opposed to the actual "hinge" type hinge.
Once that's done, so you know that the door seals will have at least a fighting chance of keeping rain out, i'd then offer up the roof. Then the overhang will just sit where it sits... not much you can do about it really.
The two small bolts either side, on the curved section of the roof, are M6
The rubber seal should fit in completely... try a little silicone lub in there, so you can "stuff" it in, and make it bunch up slightly, as opposed to stretched (so there's bits overhanging the edge)
Very rare that any LR seal will be "too much"... they'll supply and fit only-just enough to do the job, so it pays not to chop any more off! LOL!