I assume your wife drives the SUV and you drive the Stinger, correct?
What SUV and what are the actual measurements of the garage?
Stacking cars is actually a borderline-poor way to create space. I have a 4-post and it takes me about 20 to 30 minutes to take the car on the lift down and rearrange the garage. If the car stored on the lift is not a daily driver, it's not bad.
In order to avoid damage in the garage, I use two parking stops for the two cars parked on the floor. The parking stop places a car in almost the same spot every time and it's not just for longitudinal position, but lateral too. I use only one parking stop per car and it's positioned to "cradle" the left front tire. They look like this