I bought a 99 z71 with 180XXX miles on the clock. The tranny just gave out on monday and is at the repair shop being built. I have a chance to buy a 98 ls1 engine with 90XXX miles on it. Seller stated it had a ticking sound when at idle but sounded more like an exhaust leak. Its a complete longblock with truck covers and intake for 350. Should i replace all the bearings and install or should i jus drop it in?