Last night I pulled out the welder and gave welding a shot. It’s not a great looking weld but it is holding and should work great. After letting it cool and wire brushing it I gave it a few good whacks with a hammer. It is a solid weld and I can’t hear any changes in the sound of the mount while going around the edge with the hammer.
I also filled the hole that was in the metal but that was really just because I was there with the welder and could do it. I figured it would look better.
So now I have put the transmission back into place to make sure everything is going to fit correctly and also so I can mark where the bolt holes need to go. Once marked the transmission will come out again so I can drill the holes and then wire wheel the mounting plate and get it covered in some primer and paint.