Sorry, was hurrying to post before heading back out to the pool to do lots of digging (lagoon style == lots of dirt ending up in the pool, which we're trying to prevent). Anyway, here's pics as I was going. No criticism of my work please - it was my first time. It's not the greatest layout, but I was trying to work with the pipes as they were without having to add too many extra weird angles to try and spread things out). At least everything is above ground level and none of the valves or plumbing is cracked!
Tuesday morning - old pipework cut off and first set of diverter valves glued on
Tuesday mid afternoon - suction side plumbing done! Including my first error (note the coupling on the second valve from the left). I'd glued that T on first and lined everything up by eye, only to find that it wasn't level and was going to cause increasing issues on the right hand side. So recut to make it right.
Tuesday evening - one waterfall (that hadn't been attached since we moved in - had been cut off at the valve. Pipework seemed intact so I've reconnected it) and the spa returns plumbed in.
Wednesday evening (spent the morning doing other yard work, so spent about 3 hours in the afternoon on this). Connected the 2 pool returns, the other waterfall and the new return (previously the Polaris return - that's the one that involves the horizontal pipe running behind the other pipes because I couldn't figure out any other way to make it fit in the space I had)
Thursday lunchtime - hooked up to the plumbing coming from the heater (added a bypass to the those lines so that we can try Jacks Magic to see if we can get rid of some staining without destroying the heater) and finally done. Also removed the Polaris pump.
Now I just need to fill in my hole (I lost count of the number of times I slid into it while I was staring at a particularly troublesome piece of pipe). And return a bunch of extra PVC fittings that I bought from Home Depot just in case (whenever HD start taking returns again). One question I have remaining - I removed the polaris pump but I have the electrical cable running back to the Intermatic timer still connected (I've got a lock on that box so no-one tries to turn it on). Is it better to remove that cable entirely (I'm guessing yes, but that would involve more digging as some of the conduit is buried so I just covered up the end and left it for now)?