[Tweekster]

Just use the motherboard tray to take the load off of the MB.......set your motherboard into the case, mark the heatsink hole locations, remove MB and drill the holes.........fab 4 spacers from nylon stock (Lowe's, Home Depot, etc) the same length as the standoffs and superglue to the MB tray......then get long enough screws to bolt through the water block, MB, spacers and MB tray.

Or for a really clean setup, drill the 4 holes small enough, then pick up a tap (10-32 typical, I think) at your local hardware store and tap them, then install 4 standoffs......get long enough screws to bolt through the WB, MB and standoffs.

I've used both of these methods.

The downfall of a reinforcement plate is that it still just spreads the load into the motherboard.