Hi PoolDoc:

Yes the second picture more closely resembles the filter I purchased. Just take away the push-pull valve and replace it with a 6-way model and it's perfect.

I realized the first problem with switching from cartridge to de filters today. The cartridge filter has the backwash outlet on the other side. On a cartridge filter you go from pump to filter and filter to pool. On a de filter you go from pump to valve, valve to pool and valve to backwash. All three connections are on the same side of the de filter and the valve extends about 12" away from the filter. The input and output on the de filter are exactly the same height as the cartridge filter, but the valve changes things. This would be no issue if I have above-ground pool style flex hoses, but my pool is all pvc hard plumbing.

This is not going to be a diy project any more. At least not for me. Fortunately the people I bought the house from gave me the name of the pool builder. I talked to the pool guy today and he gave me a very reasonable estimate and installation time.

More to follow...