gcb 4250 overheated, calling Bob Haller please?

I started searching for info on troubleshooting a GBC 4250 and came across a few posts on here so I'm hoping Bob or someone with experience with these can help me out. I'm in Halifax Nova Scotia so I'm pretty sure I'm well outside the service area of anyone who's answering questions here. If you are local and can help, please post contact info.

It was mentioned previously that there's a transistor on the heat sensor assembly board that often needs to be replaced. I tested it and found forward bias voltages of .599 and .773. Both reverse bias and collector to emitter are showing open. So it seems to me that this is operating correctly.

Both diodes on the heat sensor also show .699 volts when forward biased and open when reverse biased. The resistor is showing 40.8 K ohm.

While I've never worked on one of these before (I'm an electronic technician in the Canada Navy) all of these seem like they're in realm of normal. If I'm wrong please comment.

The TCO is burnt so it must have over heated. My first thought is to order a few TCOs, ensure the heat sensor is making good contact with the roller and try it out. Does this seem like a bad idea? (working on mil spec kit is a little different then office supplies) The only other option I see at the moment is to adjust the pots on the PCB, but I don't even know if they control the roller temperature so I haven't touched them.

Any help would be greatly appreciated.