[Central-Electronics] Info needed on mercury batteries in the CE-200V

[JOHN D PLOWMAN]

I noticed that in the manual the refer to two mercury batteries in the limiter can and that if they go bad it will cause flat topping with speech.
I pulled the can and opened it up and the batteries are both missing and it looks like they had to be wired into the circuit board. There are two diodes that look like they are new.
Was there ever a mod that allowed the batteries to be removed or am I going to have to purchase and install new batteries?
Any help will be greatly appreciated.
Dave W4PBU