Id wait longer then that. Id definitely give it 4 days just to be safe. In my opinion it's not worth stopping your bupropion just to take some tramadol pills as tramadol isn't exactly a great high for most people. Unless you are one of the very lucky few that get a good high from tramadol it's not worth it to go off a anti-depressant that long to take tramadol. I am on bupropion and i have stopped taking it for a few days so i could take other drugs namely coke, dextroamphetamine and on one occasion tramadol. I have never in my life gotten anything but a weird feeling and also nausea from tramadol and i have only taken it when i didn't even have OTC codeine to relieve opiate withdrawals. Even at 400mg's in one dose i felt nothing opiate like from it. That is way too much to take in one dose but i am on 3 different anti-convulsants so i figured i was safe.
If you can get codeine OTC where you live that would be a far better option as atleast it gives you typical opiate like effects. You wouldn't have to stop taking the bupropion either.