What boat are you going on? Some boat captains have preferences at different times of the year, and those preferences come into play when the captain/trip has extra time to look around. Tuna (off shore or at the pens) may still be an option on a an early fall 6 or 7 day trip to Isla Cedros, and this has been a strange year. Watch the fish reports for your boat as the trip gets closer. You might still get into some variety fishing, which means everything from 20# rigs for calico bass to 60 or 80# dropper loop or yo-yo rigs.
Stoked for you! Shaping up to be an epic fall out of SD with many options on the table for 6+ days on the water.
The most important rig is your favorite "40lb" leader rig for live bait fishing, yo-yo or even casting surface iron. You could fish this rig the whole trip if you had to. 7'-8' rod rated 20-50 or 30-60lbs and a ~3/0 size reel that can hold 400yds of 60lb braid and make 15lbs of drag is a good example of what it should be capable to do.
This year a lot of smallish "schoolie" tuna so a "30lb" rig has been very popular too. At least 300 yards of 50lb braid on the reel and a lighter rod than above. The emphasis here is easy to cast light baits in a tough bite.
Other than the above good advice for iron be sure to have some Wahoo lures to pull behind the boat and iron to cast (ie gold raiders or wahoo bombs). Very likely you will spend at least some time on the hunt for Wahoo even between Cedros and SD. You don't want to miss out on a shot at them.