Its been a while since I fiddled, and now I better note done all my issues.
I found this instructable.
In order to get the device operating under SPI you have to change the configuration resistor from 8080 to SPI pads.
https://www.instructables.com/id/Arduino-Mega-and-Visuino-Connect-AD7606-8-Channel-/
Code I found for driving in SPI
https://gist.github.com/pingswept/5201193