There is no need to keep concentration as low as the oft-cited 6-8%, or even 10-12%.
With some practice lots of folks tend to handle 12-18% just fine, especially in colder weather where hydration is less likely to become compromised.
120g/hr could be consumed with 750mL + 1000mg sodium via Sodium Citrate and you’re good to go.
FYI: Sodium Citrate has about 1000mg sodium per tsp. Table salt is about 2000mg sodium per tsp.