Decal question on ECU

I would think it depends on whether the box originally mounted on the firewall or the inner fender....but then, it might not matter.
Thanks Rusty. I’m stuck inside today due to being cold out and doing paperwork at home. Saw part “a” on the window sill and part “b” on the shelf and said, “hell, I can make something happen to move forward.”
Then realized there’s more to it than just laying a decal down.