Really is pretty easy. Prob could be done in 2-3hrs if ya work quick. I just did evap and heater core in 4.5hr with couple smoke breaks and food break no rush.
The waveform of crankshaft and camshaft have a problem with sync. New ecm crank won’t start. Other shop replaced the ac compressor and busted the pigtail for the crankshaft and they installed a new one but the reverse the pins.
