Alright, so I finally gathered all the parts I need to weld on the motor mount and mount up the motor. During the test fit i'm realizing that the engine is really far to the side to center that 12x8 wheel. So basically in the pictures it shows where the supports would land to center the wheel. I just feel like it really lacks support on the right side...

So...TL;DR Will this be safe to weld and last.

 

You would need to extend the frame to the left to center the tabs over the aluminum engine mount. The way you have it in the picture, the left tabs are putting that rod or bolt or whatever in single shear and bending instead of double shear. Also, the right side mount is directly in the middle of a tube, which puts the tube in bending. This could both buckle the tube, and bind the engine mount because the tab will twist.

So no, don't weld it. Fix it so the load paths are better.

 

Here's basically the same thing you're doing, but this uses larger tubing for greater stiffness, and a good transition into the upper frame on the right side. I really don't know anything about Ruckus mods, but I know a lot more about load paths and frame design. You might be okay with larger tube for the mount bar, but that's hard to say with those plate mounts locating the ends.

 

Did you ever get around to welding it?

I was curious about the weld on kits and want to know how they handle after a long period of use.