Hi, have a good flight ! ;)

distance is 6788 sm
flying time - my estimation  - 12 hrs and 15 min
fly real weather, to benefit from westerly wind.

reserve is as I previously wrote.
alternate +-  90 miles is 2.4

you need a 200LR
max of M.82 in crz
initial crz at FL310, step up 2000 at a time,  4 times to FL390, every 2 hrs.

There is no direct commercial flight from your location to Sao Paulo, Br
If you get close on fuel, you can divert to Rio and go watch some exotic dancing girls  Oh La La !!!!!!!!!

:o  :o

If your rte is longer than mine, you have to make a correction on the flying time /  speed is 554kts

I think it will be right on.

Raymond   Boeing or nothing
KFLL  South Florida