0 580 254 910 is the Bosch "910" pump, rated to 443HP.

0 580 254 984 is the Bosch "984" pump, rated to 598HP. Thats the pump I have in my car.

0 580 254 044 is the famous Bosch "044" pump, rated to 700HP.

Bosch 910 has barbed inlet and outlet, 984 has barbed inlet and screw in outlet fitting and the 044 has screw in inlet and outlets, so you'll need to get fittings for them depending on your application (about 4 bucks each from Enzed).

To fit them in a Subaru,

1. Cut down the metal feed tube and use a piece of hose from the outlet of the pump to the cut-down metal feed tube. Small worm clamps are required.

2. Cut the plastic tab off the fuel pump sock tube, and use another piece of hose slipped over that, to attach it to the pump inlet. Small worm clamps are also required.

3. Cut fuel pump connector off and crimp ring terminals to the original fuel pump wires (supplied with pump), screw them on.

4. Use a big hose clamp to secure the pump to the pump frame.

These are all at the flywheel and are approximate figures of course. 910 will be good for 300-320 at the treads on a RWD car. 984 will be good for 350 plus, and of course the 044 when your chasing 400 plus atw.

PM me if you need one.