Installing roof truss diagonal bracing: splice plate where braces cross?
If the purpose of the plans is to just protect against damage, I think your plan is probably fine (you might not even have to cut them down to size, I don't see the problem with it overhanging a little bit).

However, it's not clear to me based on that document exactly what the purpose of the splice plates are. To me it sounds like the splice plates are on the outside faces of the braces, nailed through from both sides.

I would call the truss manufacturer to find out specifically what their bracing requirements are.