Your Summer Glow is a large shrub/small tree depending on how you handle it. Pruning every year or every other year will be about the only way to have this plant in a spot that is too small. As vigorus as it is, consider pruning it to the ground very early in the spring before buds begin to expand and grow it as a multiple stemmed shrub. In the summer prune the ocassional branch back that may get in the way using hand pruners.
You could also consider annual root pruning to slow the annual growth.