Hello, and thank you, this thread has been informative. I have an Advent 400 and a couple speakers, as well as the original manual. The list of caps will be handy, I'll be doing mine eventually. Fortunately my radio works very well and has a nice faceplate, but unfortunately the person who shipped it to me faced the knobs of the tuner toward the somewhat delicate grille of the speaker and dinged it up a bit, it was mint. All have yellowed cabinets, but I've managed to fix that without a lot of elbow grease-more on that in a sec.
First, a question: In the instruction manual for the radio, mention is made of hooking a second 400 speaker up, but no information is given as to how to do this, it says those instructions are available with the purchase of an accessory speaker. Does anyone know how? It would be handy to have two speakers running.
As for whitening the cabinets, I've used creme developer from the hairdresser shop and several hours of bright sunlight, the yellow fades nicely. I have only done one speaker (too busy enjoying the radio to pull it apart yet) and I'd say it's 80% back to white, the interior of the cabinet makes for an easy comparison. I will try and get some pics tomorrow. It's sort of hard to believe how well it works. I read somewhere that people add a little oxyclean as a catalyst, might try that also.
If nobody has done so already I'd be happy to scan/upload the manual for the radio. It's informative and very much in the Kloss/KLH style.