With planning & some room it could be very simple.

If you could mount the pump, solenoids, filters, ECU etc on a single plate in the model
you could lift the whole shebang out as a unit, connect radio leads, fuel lines & battery
& off you go. Sort of like making your own Jet Central Powerpack.

The bad news? - you will have to modify 2 models, your existing & your new one.
The good news? - you won't have to spend anything!

Yes, Velcro will be your friend. I don't know if any peculiarities of air flows or pipes
will mean any parameter changes are needed. - John.