You would have to take the aircon belt off to replace the alternator belt.

Access is a bit tight but I had no trouble getting at it from underneath when the car was on ramps.

Remove the diagnostics block and horn from the back bulkhead and your access to the belt and adjusters from above is greatly increased.

I'm not sure on the removal of the aircon belt as my car doesn't have it.

Also be careful of the connector on the side of the engine below the pulley, this is for the oil level warning light.

Mine was broken off when the alternator belt snapped.

I have since found that the sensor is very expensive from Toyota and requires the whole sump to be dropped to replace.

I've decided to just check my oil on the dipstick more often and ignore the light.
