To check for wheel bearing play, jack the car up and shake, not violently, the wheel up and down. Then spin as fast as you can and listen for any grinding noise. If its a front wheel then get a pal to 'drive' the car in the air, whilst you pinpoint the noise. Make sure your hub nut is properly tight, cant remember off hand but the torque setting is around the FT area. Broken exhaust hangers, metal bits, are easy to spot. Rubber hangers might be worn or stretched causing the exhaust to bang on the rear axle. As for the gear grinding, this could well be worn syncros. Pretty common for Starlet boxes tbh. Gearbox out job, strip down, replace and rebuild. 400 + quid area for that. Or buy a good con, few and far between, box. But before you do that i'd drop and replace the gearbox oil, around 3L of 75w 90 is required. Brand of your choice.