Don't think you'll be to disappointed once you get them wet.
Looking at the iS76 right here, the rear pad to insert / plate fit is close but no overhang. Maybe a slightly longer pad in that area could be a good mod.
There may be a couple of mm difference (or error) in the factory placement of the rear pad on your iS76 being slightly too forward vs insert positions, however this should have no effect on the use of the antitwist plate (which is buffered from contact on the deck by the pad thickness anyhow) even if the very back edge of the plate was to overhang the rear edge of the pad by a small amount.
Of course, if you have a remaining concern, or you feel the situation is different to described, please contact us further or your dealer for their inspection.
Cheers ~ Ian