89 f-350 crew, i need your thoughts
 

Hey guys, i have a 1989 f350 crew cab dullie with a bone stock 460. The truck has 130, 000 miles on it and appears to be suffering from a warped exhaust manifild. i have read alot of posts today but some are so old i wanted to ask again. so on the passengerside front of the exhaust manifold i found both bolts broken and appear to be stretched. i have a decent exhaust leak that goes away when warm but its really loud at first. this truck is very pretty with alco rims and a flawless body. when i go to fire it up at the launch ramp to retrieve the boat after a day of fun it turns everyones heads with loud noise it makes when pulling the boat with a cold motor. i bought this truck to help me with my new boat restoration venture and plan on pulling alot. so back to my question, what is the best way to fix this? i know most of the bolts are going to break and im looking at drilling. so do i pull the motor out or pull the heads off? it seems pulling the motor would be easier, also since im pulling alot with it, what can i do to get better mpgs since im already conducting repairs? i read about putting on headers but will that mess up my smog? i get about 10 mpg no matter what, towing or not

What you do to repair the problem is your choice, but have in the past either replaced the exhaust manifold or installed exh mfld gaskets and used grade 8 bolts. Both worked.