488 Does anyone know how to replace the Charcoal EVAP canister on the 488?

It looks like it is my next step. I have had intermittent trouble with filling my car with fuel, but no other issues, and no check engine lights (which confuses me because I feel like if I had a stuck vent valve, or any other malfunction, they usually come with a check engine light and codes). It seems that at least 3/4 of the time, I can't fill the tank with anything other than 1/8 - 1/4 speed with the gas pump.
Today, it went so slow, that I wound up over filling and spilled some fuel, so I got aggravated and decided to look further into it.
I started with my Autel bi-directional tool and activated the purge valve. I heard it click, so I'm thinking it's good (I know that it's not 100% normal just because it clicked, but figured good enough for now). Then I put a camera in the fill neck and pushed on the rollover flap with a semi-rigid small plastic pipe, and the flap wasn't stuck, and opened easily, so it shouldn't restrict the fuel flow in any way.
So, I'm thinking that it may be a defective EVAP charcoal canister. I know how to replace it in the 458, but I think that the 488 has it in a completely different spot (I'm pretty sure I saw it behind the driver's side rear wheel, But, not sure if I can access it from the wheel well by removing the wheelhouse, or if I have to remove the rear bumper). I can't find it in the shop manual, so I was wondering if anyone knows where it is, and how to replace it?
Also, for those that know how to troubleshoot well, do you think I'm on the right track? Can I test the canister before replacing? Is there anything I missed? Any other easy things to check?
Is it possible that the fuel vapor Seperator is bad? I know what it does, but not sure how it operates in conjunction with the EVAP canister on this car or how to test it, nor do I know if it can possibly cause the pump to stop prematurely and intermittently if it's defective.