are the tacho an speedo interchangeable?
 

i have an my 01 wrx with tacho on the right... the my05 has the tacho in the middle... are they one complete unit or can they be swapped around? can it be done ? has anyone done it?

The whole dash units are interchangeable. So you could get a dash out of an MY05 and stick it in your MY01. The odometer will be out though and there may be some wiring changes (happens when people put STi clusters in WRX's).