Here's the old set up with the 6 x 8 platform. It was too small and there was not quite enough room between the ends of the bar and the bumpers for dropping the bar and no space at all on the platform outside the cage.
I have to make a mess to improve things so the gym can get a bit trashed sometimes. This part of the mess was to create a new ladder to go from the loft to the attic crawl space.
Where the ladder is is where the new plumbing pipe ladder will be mounted. Had to use a card board mock up to get the angles right. That space on the wall between the pullup bars and the ladder looks like a good spot to mount something.