Idle went nuts.

There are two tapped holes on top of the head, meant for lifting the engine. I recall an AC bracket arm and BATT- cable often bolt there. Many have stated the FSM said to use the fwd hole for lifting engine alone and aft hole for engine + tranny. But, others found that probably refers to holes on a (rare) factory lifting plate that bolts to those two holes (someone posted a photo of that plate). Regardless, they are there to use and can take the load.