Yeah, the 24" thing is a guideline, not an absolute. If your grate is only 22" from the bottom of charcoal basket, it's not really gonna hurt a thing.
Modded Brinkmann Gourmet. Basic UDS. Rescued 22.5" OTS. SJS Mini-WSM. Stubbs. B&B Oak Lump.
Cannondale 2009 F8 (for burning off all the great BBQ)