If brushed I'd be worried that Autosol you could make that too shiny/bright.
I'd do lemon juice/light oil & foil first to see what you get and move onto something with a bit more oomph if needed. Do a test on say the underside of the downtube by the BB first less conspicuous area) before moving elsewhere.
Autosol has the small abrasive particles in, so instead choose a liquid metal polish like Brasso that won't create lots of swirl marks, that will need removing.