I just inherited my Grandpas 2002 GMC 2500HD with the 8.1. It only has 110,000 miles on it and it’s clean and kept up, only thing wrong on it is a small exhaust manifold leak coming from the back of the motor, I have all the parts and I contacted a mechanic and he said he will do it but he sounded iffy, And hopefully he don’t break one off into the head in the back because then he will have to take the head off and I’m nervous about it, should I leave it alone and continue to drive it ?

Also would i need a new manifold or have to have it machined to be flush or can I just put it back on with a 2 layered steel gasket?