I had the same issue. While I still think Teflon lines are the best, and would use them if I was starting over, I solved the smell problem without changing the Earl's lines on my car.
When I received my car back from the single/fuel install, the shop had left the charcoal cannister in place, and had the vent line from the tank connected to the rear-most port (closest to the firewall), which is the stock connection. The middle & front ports on the cannister were capped.
I noticed a mild smell of fuel in the garage starting a few weeks, maybe a month later. I contacted my tuner, they said I needed a new charcoal cannister.
Since a new cannister is ~$180.00, and I had never smelled fuel when the car was BPU, I figured I'd try a few things first before I popped for a new CC.
The stock EVAP system uses a VSV to control purge on the cannister based on engine load, mine was still on the car but not connected. So I ran a new line from the middle port on the cannister over to the VSV, then from the output port on the VSV up to the intake manifold.
While I have a V-Pro in my car, the stock ECU is also in there, and still has control over the EVAP VSV, so the Toyota purge control still functions.
For the first month or so after doing this I still smelled fuel in the garage, but less then before. I was getting ready to make the plunge for Teflon lines when I noticed that, after about 1000 miles with the purge connected, the fuel smell was 100% gone, and has stayed gone ever since.
My thoughts are that, while a new charcoal cannister would have fixed the problem, the factory knows darn well that the charcoal media in the cannister saturates over time, thus the well designed purge system that keeps the media from saturating and smelling like fuel.
I have yet to connect the front port on the cannister to the air intake (as the factory did), but I plan to do that as well.
In short, keep the EVAP system on your car, and functioning as it did stock.
Or, in my case, connecting the purge back up allowed the excess vapor in the media to be pulled out and burned over time.
