I'm going to be installing headers on my truck and was wondering when removing my stock manifolds, should I use an air ratchet to break the bolts loose or do it by hand? I just don't want any problems with breaking a bolt off in the head. Thanks.

 

I would do it by hand. The last thing you want is a broken bolt to slow you down. Take your time with the install as well, and use some penetrating lube on the catalytic converter bolts before you even try to break them loose.