I got the idea for my install from Smitty (he has a lot of posts on this forum).
He had his install done by Brazel's RV in Washington. I called the and spoke with Alan, telling him I wanted the same Fass pump that he installed for Smitty. He sent it out and I had it in two days. He told me to call him if I had any questions on the install. There were hoses and fittings I didn't use that came with the kit but overall everything but the hoses were included.
On my coach the primary and secondary filters are located in the rear passenger compartment. The lift pump pulls the fuel from the tank through the primary filter to the lift pump manifold. It then pushes the fuel out through the secondary filter into the CAPS gear pump. That's why you show fuel pressure only while the lift pump primes the fuel lines, it will then turn to a vacuum as the gear pump is pulling fuel through the lines and filters.
I as well as Smitty left the old lift pump in place and just bypassed it. It can easily be rehooked up if needed.
This is how I did it.
Fuel line from tank to primary filter is left in place.
Fuel line from primary filter to lift pump is disconnected at the primary filter and capped.
Fuel line from the lift pump to the secondary filter is disconnected at the secondary filter and capped.
Fuel line from the secondary filter to the CAPS is left in place.
Now you have a primary filter with the output port open (no line connected).
You have a secondary filter with the input port open (no line connected).
Now you install the Fass pump. These next two fuel lines will have to be made up. I used Products & Services - PIRTEK USA
Hose out of primary filter into Fass in port.
Hose out of Fass pump into secondary filter.
Pirtek had all the fittings for the hose to pump, on mine they're 5/8". I wanted to use the same size fittings so if need be I could just reconnect the lines from the stock lift pump to the filters.
For power you need 12 volts. Right next to the pump there's a fuse box. Run a fused line out to a relay.
Now you need a 12volt signal for the relay from something that's on when the ignition is on. Some people use the fan controller circuit for this signal, but I don't know if you have this.
I used the circuit for my school bus pump (the one that always fails). I removed my school bus pump so I had a 20 amp circuit available. Since it was a 20 amp line, I didn't need a relay.
Last you need to fool the ECM into thinking the lift pump is still connected. You take the relay and lift pump connector supplied in the kit and connect the line from the lift pump to the new connector. The load from the relay fools the ECM into think the pump is still there.
If you buy the Fass pump from Brazel's, Alan will give you the connector numbers on the relay.
I then installed a Isspro fuel pressure gauge to the port on the top of secondary filter. The Fass pump comes stock from the factory at about 17 psi (it's adjustable).
If you get a lot of movement in the gauge needle you'll have to install this;
Fuel Pressure Gauge trashed...