would appreciate your input figuring this one out.

symptoms are:

1) first, noticed several dash warning lights flicker at low light levels, i.e. not fully illuminated, but glowing faintly. if remember correctly, these include SRS, brake, parking brake, battery lights.

2) next day, while driving: engine cuts out (tach behaves erratically, falls to 0), no obvious issue with battery, reading 12.25V, can turn lights etc on, but:

3) won't start, with ignition key in position II, all warning lights on as normal, however trying to start the car results in only a relay click and maybe a VERY brief sound from the starter motor before total silence, all warning lights off

steps tried so far:

cleaned battery terminals
cleaned chassis ground point closest to battery
cleaned ground points on strap connecting valve cover to bulkhead
tested voltage from battery + to alternator body: 12V (so, grounded)

Unsure what to try next other than randomly replacing parts (battery, alternator)!