I believe what the OP is trying to do is avoid running into the garage entrance when bringing in the car. The ideas about hanging items or strips on the ground are all good but too late if you the garage has already rashed your fender.
I have a similar garage. With MS, I find it easier to back in and I fold the mirrors as soon as the rear of the car is inside the garage.
With MX, I can't back in as I have overhanging racks in the back of the garage so it has to be brought in front facing. Summon freaks out and at times wants to drive right into the entrance. So we always manually drive in mirrors folded. However, what we did is paste couple of styrofoam pieces at the height of the side mirror and the top of the black rim of the front wheel on the wooden garage siding that serve dual purpose - guide to how close we need to be and secondly if we do accidentally come too close the styrofoam will take the hit.
With that in place and 6 months of having the MX, we have never been too close to run into the styrofoam. After a week of parking, you instinctively know if you are too far right or left.