Where is the best place to get through hull fittings? The last owner of my boat just ran flex fittings through the transom and it rotted. Now I have rebuilt the transom and need to reattach my tabs.

Should I "glue" them in addition to bolting? Is so what silicon? What are the best fitting for the hoses?

Any help is greatly appreciated. I do not want to get in to the transom again.!