the power supply is more than the radio needs
If you're confident of this, no one reading would be in a position to know otherwise. Each of those who have replied have their own experience, and it sounds like you're sure that you're past mine.
Learning is great, provided that you don't cause yourself more cost along the way (yup, I've done that too, 'didn't listen). However, for me, when I see the task headed beyond my experience, I may be wasting my time, and it actually is less costly to have a pro do the work for me.
FWIW, Kitchener Aero repaired my KY196 last year for $300, and I was entirely happy with their work.