Thank you everyone for the help.
The part was about in the midddle, a foot down from the top. I had to take the back cover off. No big deal.
The customer had two nice 6 X 6 pieces of wood, that stood on top of each other, lying down, carefully balanced the oven for slide out most of the way. Enough
so I could get the back off and change the part.
Pretty smooth sailing. Potential to be a bear in other circumstances I'm sure.
Bruce in L.A.