Realistically speaking it's a much more realistic
From a logistics point of view, I will agree that it's way easier sneaking away just after the ceremony and utilize the photoshoot time to get her blacked. I wouldn't mind paying the photographer extra to capture her naughty moments too, provided he signs a confidentiality contract, but letting other people know (eg. bridesmaids, makeup artist, etc.) like other people suggesting is way too risky.
However, I understand that the "after wedding" scenario might be less exciting for both of you. I guess, that watching the love of your life walking down the aisle with her proud pappa on her side, clueless that he raised such a BBC slut, is such a satisfying feeling. Equally on her end, the thrill of being mercilessly fucked with your future husband blessings, only moments before exchanging vows with him, is a truly empowering moment that you will both recall forever!
To be honest, as much as I wanna see this working, I can't realistically think a way for you to make it happen without the risk of her being exposed. I personally wouldn't have an issue with inviting a black man or two in the wedding (you can always find a reasonable excuse to justify their presence), but on a day which a wife becomes the centre of everyone's attention, the level of difficulty to pull this out becomes a mission impossible.
