1) Adjust the white plastic screw to allow the mech to accept a token slightly larger than a quarter. I had to turn it about 5 degrees clockwise if I recall.

2) I am not sure if this is necessary for everyone, but I had to fiddle with a second adjustment at the bottom in order to get the mechs to take both quarters and tokens. I think this is a step that checks the weight of the coin. It took me a good 30 minutes to get both of my mechs just right. It is just trial and error.

At the end of the day, about one of every 25 tokens/quarters doesn't pass. This is close enough for me.