Every 4 weeks they have you doing 60% for 5x10. That's a little heavy and a little voluminous for a deload, but I think it still technically counts as a deload. I don't know if you would actually need to add a deload for week 17 or not, it all depends on how you feel. Throwing one light session in won't kill you, and it won't detract from your strength levels either.
As for your question of how much to jump up, I would suggest hitting 4 singles: 75%, 85%, 95%, and then 102-105% of your old 1RM. If you're not feeling super powerful after your 95%, err more towards the 355-360lb range. If you smoke 95%, try to put up 365-370lbs. A 15-20lb increase on your bench in 4 months is pretty good, especially when you're tall and skinny with a 350lb max already.
The best advice I can give you for maxing out is something you probably already know, but I want to hammer it home: warm up with something other than bench press. Obviously you're going to need to warm up with some benching before you test your max, but jump rope for 5 minutes, or shoot hoops for 15 minutes, whatever; don't just hop on the bench and try to get after it as soon as you step foot in the gym. Get your whole body buzzing, and then smoke a PR.
Since you're still hitting all your numbers after week 10, I'm sure you'll be able to finish the program strong. Good luck man, and don't forget to use a spotter!