hermco bracket

[captkev111]

I am going to be installing a hermco fiberglass bracket on my 1986 23 seacraft walkaround
....I currently have a 250 verrado on the back and it has sank 2x on me I think do to the engine being to heavy on the back of the boat ....I was wondering if anyone has any thoughts .....do you think I should go with the double bracket to get more flotation or just go with the single bracket.