Yuhm, yeah. Took like three weeks to change the heater core on my beater Audi. It was my primary mode of transportation. (was quoted 8 mechanic hours).

I spent like a frustrating week trying to figure how to get a wire harness to come free; Later I learned that the guide I used, they had an important bracket that had broken for them, and was skipped in the guide and working fine on mine. It was like performing dentistry using an endoscope from the other direction.