People are always asking me what I use to polish and clean guitars in my shop. Most people don’t have a professional buffing machine in their home and it is really hard to get a good clean shine from the store bought guitar polishes, especially if there is a heavy grime build-up on your instrument.
One of the best consumer products I’ve found comes from the automotive supply industry from a company called Meguiar’s. Their Mirror Glaze line is amazing for cleaning and polishing guitars.
I find that to get the grime off and leave a lovely glossy patina, their #7 show-car glaze is wonderful. You may need to apply it several times wiping it down with a soft polishing cloth or regular white paper towels (they work great), but you will wind up with a deep rich shine in the end. For an even shinier look, their Plastic Polish #10 is as shiny as can be. I prefer the #7 for vintage guitars. You don’t need to polish too often, just a few times per year to keep it nice and clean. These products work wonders on fingerboards as well! Search the web or use this link to order these at meguiars.com
All the best, Scott