Just wanted to mention, that if the output of this machine is able to inflate the bag on Art's DC then it is putting out quite a bit of CFM. A shop vac will only do about 100-130 cfm with a short 2" hose and a filter in place at best. The shop vac would not be able to keep up with the volume of air.
I've got a jet version of the 2 stage garbage can lid separator mounted on a rain barrel. It works great though it is hooked up to my 2hp dc.
If I were to go with your good idea of hooking it up to a two stage to collect the chips and dust I would attach a shopvac filter on the middle (now exhaust) port on the lid so my shop didn't fill with what little dust tried to escape. You might also want to weigh down the lid so nothing leaked out the edges.
This is just my untried idea so take it for whatever it's worth.
Let us know how you like the planer, I'm tired of coaxing along my belsaw. By the time I bought all the parts to repair it I could buy a dewalt or a new steelcity with the spiral head. Still going to keep it regardless, it was my grandfathers, but tired of having to adjust and fix every time I want to use it. I'll turn it into a restoration project as soon as i have a replacement.
That's not even a smile! That's just a bunch of teeth playing with my mind!