Using a rack for power amplifiers and power conditioners

I have a Cerwin Vega CVS-21S and I am wondering if I can’t put a rack on top of it or can I put a rack on top of a Cerwin Vega XLS-215 or on a Cerwin Vega EL-36DP folded horn, the powers amplifiers I am talking about is crown xls 2502 with crown xls 1502 and crown xti 6002 and for the power conditioners I am using furman pl plus dmc 15 amp version 3 of them