There are dots on the speedometer that tell you how fast you can be in each gear. I have one dot at about 65 km/h, indicating I can be in first gear up to that point. The engine will be at its max. rev point at that spot. I have 2 dots at 115 km/h and 3 dots at 195 km/h for second and third gear respectively.
So if you need to go uphill and your speed is below that 2 dots on your speedometer, it is save to shift manually into 2.
I don't know the 180 engine, but second gear should be good for 70 km/h.
Give it a try.
Now weather your transmission is adjusted properly is another story.