Transducer mounting board?

[311Hemi]

I am installing a transducer mounting board and am curious if it's really necessary to install screws into the multiple holes that I will be covering up with the board. I have read multiple posts of guys saying they would install screws and then countersink the back side of the board so it would sit flush on the transom. Just curious if this is needed if I plan on using 3M 4200 on the back of the board (all around the edge and in the new screw holes) and then running a bead of it around the outside edge after it is installed. I will probably screw it as well.

Thoughts?

[PerchJerker]

I always put screws back in the old holes, with a dab of silicon. It's the best way to make sure the holes never leak. Do you HAVE to do it -- probably not, but I would.

[CAMAN]

If they were big holes (1/4"+) I would plug them and silicone them up, but being they are just small screw holes I would squeeze some silicone into the holes and put some generous dabs of silicone around them. As long as the board is tight against the transom you shouldn't have any issue with it. But if for some reason there is a gap that you can't get rid of I would plug it with a screw.