Re: rear light problem
Depending on where you live there may be a small TV repair shop, or a local electronics factory that employs solderers who could do a homer, you would need the replacement transistors (exact same code or exact equivalent - if they are unmarked, your screwed) and they might not be the only damaged components.
BBA-Reman will recon the instrument for you, couldnt say the exact cost but will be cheaper than a new one.
A local TV repair shop will not have access to schematics to properly check the circuits and will likely refuse to try or to guarantee any repair if they do.
Im a professional electronics engineer, and believe me its very difficult to properly test all the components on a circuit board without a schematic so you know whats connected to what, as this changes all the readings from a component measured on the bench.
Transistors - especially small-signal silicon types (little black three legged-job), are notoriously difficult to match if they are blown and dont have their part numbers on them. They come in a MASSIVE array of options like operating voltage, current, gain, signal rejection, polarity etc, you get the idea. There are over 20,000 different models/part numbers just for these alone.
Best advice is if you can get them, and know what they are, and get them replaced on the side by a friendly solderer, then go for it. Otherwise, give it to a specialist or get a rev counter off a scrapper.
Me & Her...
I love my tractor so much, If it wasn't an abomination o' god's law, I'd make it my wife...