Good job, Zen....
You can have my job if you want it....

There was time in my life that I wanted to be a mechanic. I even spent a year at Walker Tech and graduated on the Director's List. They said I was the first student to graduate the auto mechanic's program with a 4.0. The biggest thing I learned is that while I could do just about any job thrown at me and usually did excellent work, I was WAY TOO SLOW to make a living at it.
I've been told this Heater Core job is an 8 hour job. I spent 8 hours trying to figure out where the last 3 wires plugged in. I wasn't working on it solid, and I spent about half of the time I was "working" on it at the computer looking at the manual or doing "research" on the internet, and there were a couple of days I didn't touch it at all and a couple of days the rain really limited what I could do to it, but still . . .
it took me 12 days to do an 8 hour job. Since I had the time off and probably wouldn't have done anything else productive, it was still worthwhile for me, but the bottom line is, I like to eat. I wouldn't be buying many groceries on what I could earn as a mechanic!