I have the R1C1 with 5 Sr-200's. I have tried to shoot pictures with the 200's in many different positions all has bee fine except when the 200's block the IR transmitter of SU-800 commander. Will the Sc-28 or Sc-29 cables work with the SU-800? I placed my SB-900 in the hot shoe and the 200's blocked the transmitter as well.
I assume you have the R200s on the ring around the lens? Yes, the SC28 will work with the Su800. Also with the SB900. You can mount the SU800 or the 900 on a bracket attached to your camera, or on a nearby light stand. You'll be limited by the length of the cord of course. I am toying with a setup using the foot that comes with the SB900. I'll take a photo of the setup I made.