Grind away part of deck stringer to install backing plate?

[Stumble]

Barry,

Before I would touch a stringer with a grinder, I would have a navel architect certify that it wouldn't compromise the boat. There is just no general rule of thumb here.

But conceptually, you want to mount a highly loaded system into a newly weakened area of the hull? Sounds like a recipe for disaster to me. Without professional advice I would say only option 2 would be acceptable.