You should find a blanking plate clipped under your windows, use them to cover the holes that are left in the shifter, and fix them with one of the original screws. If you undo both of the 4mm headed bolts, the clamps will pull off, replace them with the Hope mount which will then replace your lever clamp (if you’ve bought the correct ones).
Edit- the blanking plates are “handed”, make sure they go on the correct side or they won’t fit correctly. To prevent losing the other screw, you may want to screw it into the redundant hole on the shifter, if so, be aware that fully tightening it sometimes causes it to catch on the internals and jam them up, backing it off a turn will sort it.