The trunk light is, I believe, on the taillight circuit.
Also, if it's JUST the dash lights that went out, there is a transistor mounted on a heatsink, above the driver's right leg.
The whole transistor/heatsink is removed as an assembly. The transistor (a metal, diamond shaped thing) can then be unplugged from the heatsink after removing two hex screws.
The white stuff is thermal compound. Needs to be there. It is NOT corrosion.
When you unplug the transistor, be careful not to damage the quartz insulator that is between it and the heatsink.
What usually happens is that the pins will gradually get an intermittent connection in the sockets. Usually, bending the pins just a bit will help the connection when it's plugged back in. I soldered my pins after plugging it in.