I'm not seeing the other part number listed anywhere for a B/D body (on rock auto anyway). I tried 94, 95, 96 fleetwood and 96 impala SS and the only part number Rock Auto showed me for Spectre is the SP128 one. If you look at amazon, the dimensional specs for the two pumps is completely different. Not really sure though, other than calling Spectre direct, but if it helps at all I just ordered n SP128C1H for my 96 Impala SS. lolWhile browsing RockAuto, I realized that there appear to be two different senders listed for the 94-96 Fleetwood. Part # FG128C under "Fuel Sending Unit" costs $116. Then, under "Fuel Pump & Housing Assembly", part # SP128C1H is listed for only $78. The pictures look identical.
What is the difference?