Got the starter back from D and D auto electric ( actual name!) He showed me where the brushes articulate that there was some melting and said what you guys recommended- add a thick ground wire. The armature was damaged but he had another one reconditioned to put in. Also the end cap with brushes needed replacing.
Another question. Where would you recommend to attach the additional 00 ground wire to the engine? I see holes in the cross member under the engine for one end but where on the engine or sm420 do you recommend attaching?