Brake Master position
Space under the dash is even tighter.
The factory did make a vertical offset mount for under the hood to raise the master and or the booster. but to use it you have to use the matching small diameter booster, which is a dual-diaphragm, which in my experience does not do well with a low manifold vacuum signal.
Here is a pic of a similar unit;
![back-hemi-booster.jpg back-hemi-booster.jpg](https://www.forabodiesonly.com/mopar/attachments/back-hemi-booster-jpg.1715786436/)