Can't help but wonder

[aunt betty]

Your gunna love this cut. Had to though. The transom was wider on the bottom. the corner plates are just placed there. not laced down yet.

In as helpful and nice a manner as possible...I suggest re-cutting that piece. Use the first piece as a pattern and make marks on it showing where, and how much bigger to make it. Good "joinery" requires tight fits for friction to take place. Friction is what hold everything together. The nails, screws, or glue just pin it in place.

I've had to do a piece over before and I think you should do-over. It's GOTTA hold or you will die.

P.S. How did you get it in? Those braces are welded? I don't see how a perfectly fitting piece would get installed. Maybe I need to look at better pictures. (trying to help, really) I get it...the corners aren't welded. I know a guy who works at a boat factory. You need his help.

To get the old one out I had to cut it in pieces and it only came out easy cuz it was rotton. The only way to get it in one piece perfect fitting would be to remove the riveted braces and there is no way I was doing that. It is good thick aluminum and in great shape structurally. Do you really think it will fail killing me?

Naw. You can swim...right?
Take it easy...I'm just messin with ya now.

[Mornin Beef]

The lake will swallow the bow first anyhow.

[aunt betty]

MB. My first boat...the transom broke while I was out on the water. Almost lost the engine too. It was someone else's boat and my engine. They were glad it broke on me, not them.
Here's what I would do.
Test your repair on the boat ramp. TRY like hell to break it by revving your boat motor. Keep the boat on the trailer strapped down when you do this.
If it don't fail on the ramp, chances are you'll be fine.

I have a hard time calling an internal combustion engine a "motor" because it's on a boat. Awkward.