depends on what amp.. you didn't state what brand.. but seems like you're referring to sundown.. you're probably looking at around 4200 maybe 4300 is my guess the amps are underrated..
i met my ex wife at my work place , i was her boss, but at work i treated her as my co worker, at home i treated her like a wife, she was cool about it. But thank goodness i'm not with her anymore....
DO NOT let your buddy screw them in at an angle you will most likely make it worse there will be weak spots in the wood and it wont last long before the sub beats the box to hell i learned this that hard way
x2 don't have him screw them in at an angle not really your best option, use it as a last resort if you don't feel like making another sheet to put on top of it...