Need some help.

Have a Sears Kenmore built in double oven. Top is electronic control, botton is manual control. Top oven sensing wrong temperature. When we turn it on to a temp, say 350, it is already sensing 465. The preheat beeper will go off immediately. The only way to get the oven up to temp is to set it very high, say 550. Then the oven continues to climb and will not shut off.
I have checked the temp probe sensor in the oven and it checks out ok. The schematic calls for it to have 1100 ohms at room temp and 2650 ohms at "clean" temp. I checked and the probe reads right on at room temp and at roughly 600 degrees checks close to 2400 ohms. I don't think the probe is the problem. That leaves the control board P/N WB27K5091. Checking APP web shows that part to be a "Call for special instructions".
The lower oven is fine but it has a manual set thermostat.

Do you think I have trouble shot it correct?
What would be the special instructions beside the part number on APP web site?

Here is the contact information on the company that rebuilds clock/controls made by Ge that have been discontinued. I actually found them on Ebay and haven't tried them yet, but I have a customer in the same circumstance and going to see if they want to give them a try.
[EMAIL="info@generaltimerepairs.com"]info@generaltimerepairs.com[/EMAIL] or call 712-792-1248 You have to have the information from the back of the control itself!

If it works let us know, ther's 1000's of people out there with similar problems.
Nat