Greetings,
 
Well, I've still been trying to figure out how I could get two EWP's in the RV-3, and took another look at the Meziere WP136.  It seems pretty comparable to the Davies Craig unit as far as specs, but there are some advantages/disadvantages to each.   Primarily, the Davies Craig is much lighter, but the WP136 has threaded fittings.  I also like the inline orientation of the in/out fittings on the WP136, which might allow me to fit two of them on my firewall.  All the pictures and measurements in the world can't answer the fitment question as well as having one of these in my hand, so I ordered a WP136 from Summit today (should arrive Friday).  I'll take it to the hanger this weekend, and see how it fits.  I can also imagine a number of mad scientist experiments, including temporarily hooking the WP136 in series with the flow meter (arriving later today) in my system on the plane.  This would give me 3 pumps in series, along with a flowmeter.   I can also play with each pump and the flowmeter using a bucket of water, and my spare evap core.  Rusty (fun stuff that I don't have time for)