I repaired my AM-8 track radio. The Sam's book is a great reference. Lots of pictures and all of the component values are stated.
Replaced a few caps, one had actually blown and leaked electrolyte all over. A few others were bulging at the pressure relief, so I replaced those too. Connectors had been cut off when this radio was given to me, I repaired with modern connectors, and also put mating connectors on the car harness.
Had an intermittent issue with one of the speaker outputs dropping out, turns out it was a mechanical problem with a Motorola transistor (the round guys with the two screws holding them to the radio chassis, just above the volume and tuning knobs). There are a couple leads on the back of the transistor, these are supposed to be insulated from each other as well as chassis ground, found that the cloth insulation had slipped back and two of the leads were shorting to each other. It was a real obvious fix and the best part was the cost, $0. I had researched getting a replacement transistor and they are still available.
Other repairs performed was a new belt for the 8 track and new string for the tuner.
Some pictures:
1 - blown cap, vented at pressure relief
2 - brown/black electrolyte leaked out of cap
3 - overall view
4 - real connectors
5 - testing
6 - installed