I bought a 2008 Cobalt with a blown 2.4 engine with 71,000 miles. I believe the timing chain broke. I found a new engine with about the same miles. I am going to swap the engines. What else should I replace. I would guess I should put a new Chain and tensioner, thermostat and all the belts. What else should I do while I am in there? I am fixing it for my daughter.