There are a number of ways and if you ask five mechanics, you may get five answers that are the best way.
However, I have done it from underneath but if you don't have a car lift then this is pretty difficult.
The other way is to literally lay on the engine and do it by feel.
The last way that I have had success is to remove the wipers and cowl panel and then that will give more room.
I am attaching the info below from the manual. This gives a little more detail on how to do the rear bank.
Please let us know what you find with this and if you have other questions.
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Wednesday, November 3rd, 2021 AT 8:33 PM