You should be aware that there is a certain mortality rate in practice single engine go-arounds in piston twins. I once saw the remains of an Apache that cartwheeled on a practice single-engine go-around. A few years after that, an inspector and candidate died attempting a single-engine go-around during a flight test in a piston twin.
If the instructor/inspector says there's a truck on the runway after the wheels are down in a piston twin, tell him you're landing on the grass.