Hi Spratt,
I was in a very similar position to you about 15 months ago, with a CDS3/555PSDR, 52/SC and NAP135 power amps.
First, I would skip the NDS. If you want to stay with Naim for streaming, then I would go either ND555 or NDX2 for well documented reasons about the much better streaming module in the new streamers.
Here’s a link to our journey into streaming from the start point of a CDS3/555PSDR.
A journey from CDS3 to a decent streamer
Hope there’s something in there for you.
Best regards, BF