Remove lower unit on 1990 90Hp Mercury outboard

[lrosa]

I am trying to remove the lower unit on my 1990 Mercury 90hp. I removed the 4 bolts and 1 nut, but it is still not budging! I tried WD40 and Liquid Wrench and using a 2x4 to try to pound it off. Does anyone know if there are additional bolts or something else that I can do to get it off? I am trying to replace the impeller. thanks in advance.

[Beachcomer]

Check YouTube....several videos explain....bolt under trim tab