I would actually keep the CD3 and get a decent DAC (better than the DAC in the CD3). I bet the CD3 is great as a transport and if any upgrade is needed, it would be the DAC. Also, a REF 3 or REF 5 would be a definite upgrade. But, listen to a REF 3 and REF 5 in your home if possible with direct comparison with your LS26 first.
enjoy
enjoy