I have the LaCrosse 303RKS rather than the Tracer 3150BHD, but I would imagine the height is about the same. I did measure mine this year and if I remember correctly it was around 11' at the AC cover. I believe the AC cover and MaxxAir covers were about the same. Should have written it down.
I had my cover built with 12' sidewalls, just in case. The pictures below are not the best angle but I believe you can see that the MaxxAir covers would clear the 12' sidewall height.
I would measure the door opening to be sure it's 12'. Then if you think it's good to go, have a spotter watching close as you back in.
Thought I should add that I have not
measured my sidewalls to see if they are exactly 12'.