Pulpmillguy
Journeyman
OK, I guess I went the extra mile and made sure everything was isolated. Here you can see the white bushing under the washer on the outside cap.What you have implemented should work, as long as the bolts are isolated (the pictures don't show under the bolt head).
I do not isolate the transformer core or cradle from chassis.
Each plate within the transformer lamination stack is isolated to help minimize eddy currents.

Which is the bushing on the right side of the bolts below: As you can see all of the bushings extend into the core laminations to make sure everything is centered and isolated.
