I know people are much more into aesthetics than I am, I'm a form follows function guy. My rack is wide open both for cooling and flexibility. I designed it myself and had it fabbed in a weld shop. It doesn't look nearly as bad as most are imaging now. Painted black, it mostly disappears.
So my first suggestion is bet a bigger rack.
But I realize i'm the one here that is not normal and so you'll probalby keep the rack. Gooogle quickly finds lots of options. But most are cheap and certainly not the high end audiophile quality connectors that many of us use here. The best quality available, that I could find, which isn't bad, is Neutrik.
I would not use an adapter but would instead replace the connector with a right angle connector from neutrik.
Best of luck
Jerry