Howdy dude,
If I was you I'd start LST'ing the one on the right, but why not do both??
Also, just a friendly word of warning, if your putting your plants outside during the day, as I do, and especially on the grass, have some on standby to combat spider mites...... just in case.
Don't wanna get caught by an infestation while your flowering as I did last time. Protein rich pot.....
Go on a Ladybird/bug hunt in the garden and keep them dormant in the fridge. (still have to feed them tho)
Peace