I hear ya! I've got what will probably turn into at least a two year whole property rehab if I don't run out of budget first.

Yeah, that's what I had in mind, but didn't think it out before posting. What I had in mind makes for a ~40" wide speaker at the wall junction due to the size of the 604 if an ideal 45 deg angle is used. Any angle is better than none though, so make the internal depth and baffle proper only deep/wide enough to mount the driver and the angle is whatever it is with the widest 'base' that can be tolerated.

GM