I have 2001 Chevy 2500HD Silverado. It needs a transmission rebuild, head gaskets, and injectors. It also has an intermittent factory security problem. I need a mechanic capable of doing this, preferably Duramax specialist. I am located in MD but willing to travel a decent distance for the right mechanic. I called Maryland Performace Diesel multiple times, but they refuse to call me back with estimates. Who would you recommend?