I would not worry about it, have spent a lot of time flying in Africa single pilot stuff in a little twin turboprop and usually wore jeans and a t-shirt. Never once had any trouble that some stripes would have sorted out. Be polite and big up their ego letting them know you are thankful for their favors and you will be fine. If you have the attitude that I am the captain and I demand you let me do so and so there are not enough stripes in the world that can help unless of course they are actually solid gold then you can pretty much do what you want in Africa.