I've had a FACET pump plumbed into the fuel line on the 100 as a backup to the SU for almost 10 years and about a year ago I actually had to use it when the power lead to the SU vibrated off. I have an "On-Off-On" switch in the bulkhead behind my seat so I only had to reach behind me to turn on the FACET but its continuous noisy running made me think of a more "elegant" solution, hence my initial post on this topic last November.
Well, it took me a year to get around to it but a few weeks ago I finally sent Dave Dubois the double-ended SU pump that I bought at a swap meet several years ago for $10.00 and I got it back from him last week. He did a nice job of rebuilding and refinishing the pump and converting it to solid state.
These pumps were apparently used on cars with two fuel tanks and were plumbed with separate fuel lines with both ends running simultaneously. However I told Dave to set mine up so that only one fuel inlet was necessary, my intention being to again wire it with the "ON-OFF-ON" switch so that one end would be the "main" and the other end the "backup".
Today I removed the SU and FACET and I plan to mount the double-ender on top of the left-hand battery tray which has been empty since I replaced my two six-volt batts with a 12 volt unit some years back. I'll post some photos when I complete the installation.