Accuphase E-470

Lloyd, I doubt that placing the connections of the 4ohm speaker to an 8ohm tap will cause any harm.  However, if you are concerned about the potential of harm then reach out to Upscale Audio again and ask that question.  They are very well informed on both of the brands in question and will surely provide you with a correct answer.  AS long as there is no potential harm then make the connection and give it a listen.  Maybe you will be satisfied to a point there is no need to change out your equipment.
Best to you.

I regret the day I sold my stack of Accuphase components to my nephew.  I have had several really great systems and my Accuphase stack was probably the best (until my newest and latest BAT system).  Accuphase has a wonderful sonic signature and the build quality is superb.  However, I really don't recommend buying any unit that is not made for the U.S. electrical system.  If you really want Accuphase then search for a U.S. model.
The Focal speaker line is rather efficient, most models at 92db efficiency, and delivers very good "slam" at low volume.  But of course, "slam" is relative to what one desires.  I personally like my music to be played with some good current delivery and, thus, keep the volume up a bit getting me some good slam.  Upscale Audio sells a ton of Prima Luna combined with Focal speakers.  That seems to be their go-to speaker brand when selling PL integrated amps or component amps.  Be sure that you are connecting the speaker cables to the correct taps on the PL amp.  For those speakers the speaker cables should be connected to the 8 ohm taps.  Unless I am incorrect, I believe that your speakers are 8 Ohms, nominal.  Check the speaker specification, check your connections, then try some more listening, just to be certain.
Good luck on your quest.