The steel exhaust header bolts on my motorcycle are extremely corroded and either have no head, or I expect they'll round out. I'm planning on drilling their heads off to release the pipes and allow me to remove the cylinder head to work on it off the bike. Before taking it to a machine shop to drill them out, I'll try stick welding nuts onto the remaining stubs. First question is whether anyone has any tips on positioning the ground clamp. The outside of the head consists of aluminium cooling fins so I'm not sure I'll have room to get a clamp on those. I'm thinking on that timing chain nose space bit? (see attached) Second is whether I need to mitigate the head distorting with the heat, or if this is unlikely. Lastly as I'll be stick welding with 6013 rods, is whether there's a recommendation for DCEP or DCEN?