Cal audio ssp 2500 for SACD multi-channel


I have a cal audio ssp 2500 that I love for HT and 2 channel. I now have a modified Denon 3910 and would love to be able to use the 2500 to pass through the multi-channel analog for SACD from the 3910. The 2500 does not have a multi-channel pass through.

Any suggestions?

Thanks.
jmpwme
Thanks - I've already talked to scott. He'd be willing to assist with schematics, but is unable to do the work.
I would be interested in doing the same thing with my cal ssp2500. Were you able to get an answer if msb would install a 5.1 input to the cal?
thanks,
Michael