Need 5MT WRX Gear ratio. please help

[svxaddict]

i have a 2003 wrx 5mt that i want to install i need to buy a rear differential i need to know the gear ratio.. i heard it was 4.11 is that right?

any cars it will fit the wrx transmission...?
which cars will it fit from to work with my 2003 wrx transmission? any nissans? any subaru's?

[XT6Wagon]

2003 should use a 3.545 IIRC. I would check to see what the transfercase ratio is, since IIRC the 2003-2005? had a 1.1:1 reduction making for a 3.90FD, with 3.90 front diff, and a 3.545 rear diff.