Because the value of a capacitor is what it actually measures, not the value printed on the case, always use a capacitor meter to check the capacitors you install. For example the actual value of a 10% tolerance 2 microfarad capacitor can be anywhere between 1.8uF and 2.2uF and be in spec. This would change your system balance if you had installed the 1.8uF in one channel and the 2.2uF in the other channel.
For best results install the new capacitors as matched pairs, channel to channel, to make sure both channels are the same.