I presume you are fitting the Pazon "Sure-Fire" system (as the Smart-Fire system includes a special dual output coil)?
Both coils should be identical? And, as you will be rewiring them to work in series with the Pazon kit, the coil numbering is not really that important, as both coils produce a spark together each time, so whichever coil you connect the red Pazon box wire (+) to, can be considered to be the No.1* coil, and the other No.2.
What is really more important is that you connect the wiring to each coil (+ & -) terminals as shown in the Pazon diagram.
As your Commando is a 1970 model I expect it still has Lucas 12V coils? (check the numbers on the base of the coils)
Wiring two 12V coils in series may give a weaker spark than two 6V coils, as was used on later Commandos from 1971-on which also incorporated a ballast resistor. The Pazon instructions (note 7) says to disconnect the wiring from the ballast resistor, however as yours is a pre-'71 Commando then it shouldn't actually have one!
The Pazon instructions also mention that 6V coils (or a 12V dual output coil) are recommended, so it may be worth changing the coils to get better sparks if they are 12V?
*Coils are generally numbered according to which cylinder they serve, however for some, that is understood as being numbered from left to right as you sit on the bike, but for British bikes it can actually be the opposite way, the cylinders being numbered right to left as Triumph/BSA Triples are!
A quick look through the Norton service manuals, and the cylinders only appear to be referred to as either 'left' or 'right'.