I am wanting to change the heater core in my 2004 Suziki Forenza myself. I am looking for a maintenance manual for this model vehicle or someone with the knowledge of how the dash comes off.

There are no Haynes manuals for Suzuki Forenzas. This is a very common problem people run in to. Go to their website and you'll find that out.

Removal1)Disconnect the negative batterycable.2)Remove the instrument panel byremoving the screws and the instrument cluster trim panel. Disconnectelectrical connectors. 3)Recover the refrigerant.4)Remove the heater/air distributorcase assembly.Heater/air distributor case assembly removal: a)Disconnect the negative batterycable.b)Remove the instrument panel andtie-bar. c)Drain the cooling system. d)Compress the heater hose clamps atthe firewall and slide the clamps toward the engine.e)Remove the two heater hoses fromthe core pipes at the firewall.f)Remove the screws that secure theheater/air distributor case assembly to the firewall on the side of the heatercore pipes.g)Remove the high-pressure andLow-pressure pipe from the A/C expansion valve.h)Remove the evaporator drain hose.i)Have an assistant support theheater/air distributor case from inside the vehicle.j)Remove the screws that secure theheater/air distributor case assembly to the firewall on the side of theevaporator.k)Disconnect the rear ductconnector.l)Remove the heater/air distributorcase assembly from the vehicle.5)Remove the wiring harness andelectrical connectors from the heater/air distributor case assembly.6)Remove the screws that connect theheater core housing and the evaporator housing.7)Separatethe sponge from heater/air distributor case assembly.8)Remove the heater core coverscrews from the heater core housing.9)Remove the heater core.Installation1)Install the heater core into thecase.2)Install the screws on the heatercore housing. Tighten: Tighten the heater core cover screws to 1.2 Nm (11 lb-in).3)Install the sponge onto theheater/air distributor case assembly.4)Install the screws that connectthe heater core housing and the evaporator housing. Tighten: Tighten the screws to 1.2 Nm (11 lb-in).5)Connect the wiring harness andelectrical connectors.6)Install the heater/air distributorcase assembly.7)Install the instrument panel.8)Fill the cooling system.9)Evacuate and recharge therefrigerant.10)Connect the negative battery cable.

You can go to any auto parts store and buy a haynes manual for your specific vehicle. they are based on a complete teardown of vehicle. the manuals are only about 20 to 25 dollars. have a good day !! ( then you will have it just in case something else goes wrong !!)