Atf for 904/999 transmission

I know im beating a dead horse reopening this thread but I just want to make sure I'm not screwing up anything. So by the recommendations made in this thread im gonna switch to the type f fluid. Is ok to mix the type f and atf4? I dropped the pan but im sure the converter is still full of atf4. I also have a couple quarts of atf4 I drained from the pan will it be ok to mix the two? Thanks guys