Also the carpet and cloth surfaces tend to hold smells much worse than the leather. I know you said most of the scunk smell has diminished, but if it's lingering in the slightest it will mask the pleasant smells of everything else. After I've detailed my interior someone will jump in and be like "ah love that new car smell". To be fair it's only 8 months old, but the "clean" smells of carpet cleaner, leather cleaner, vinyl cleaner, and window cleaner combine to make a pleasant "smells like new" because it doesn't smell like anything foul smell.
First off I have done this before selling a car. I vape quite heavily in my car during my commute. Remember smell are particles in the fabrics of the car.
#1 - Steamer and Steam Cleaning System
*I used a vaccum with a steam cleaning attachment.
You want to steam clean all of the carpets and every surface that you can get on. You want to use something with a bland and restorative effect. Steaming the FOAMS in your seats can kill bacteria and re-invigorate the foams to make them Fluff Up. (This is why I tend to buy cars with cloth seats and cover them in Katzskin. Over time your foams will be crushed but the katzskin can be removed (since they don't usually remove the cloth from the seats and the foams steamed to fluff back up.
OxyClean and steam clean the carpets including the roof panels.
MAKE SURE YOU STEAM THE TRUNK. A lot of people don't do this and as a result the smell remains and permeates the rest of the car. Don't belive me? Spray something in your trunk and then sit in your drivers seat.
#2 - Once you have done this you want to leave your car locked up with a dessicant of your choice. Dessicant's are a hydroscopic substance that captures and dry's out an environment. They are usually silica based. (Think of those little packets that come with some products like sneakers in the box that say do not eat.) They are there to absorb any moisture created during the sneaker's creation and dry it out. They also stifle and absorb smells. This is your main weapon to try and pull the smells out.
#3 - After you have done the initial cleaning remember to prep your surfaces with a good leather cleaner and to clean your carpets with a good carpet cleaner. After doing this regimen a few time EVERY Time you sit in your car it should smell brand new.