I've done it; fairly recently in fact.
Trans and rear diff need to be swapped, computer and entire front body and engine wire harness and the dash harness need to be swapped, as does the cluster and a host of other things.
It's not terribly difficult, just time consuming and you pretty much need the donor car beside you (how I did it). I would NOT buy a used H6 engine only with aspirations of shoehorning it into an H4 car. You will go broke buying alll the stuff you need but didn't get.
http://www.subaruoutback.org/forums/110-gen-2-2000-2004/47861-transplanting-h6.html
Rolled LLBeans are cheap
Trans and rear diff need to be swapped, computer and entire front body and engine wire harness and the dash harness need to be swapped, as does the cluster and a host of other things.
It's not terribly difficult, just time consuming and you pretty much need the donor car beside you (how I did it). I would NOT buy a used H6 engine only with aspirations of shoehorning it into an H4 car. You will go broke buying alll the stuff you need but didn't get.
http://www.subaruoutback.org/forums/110-gen-2-2000-2004/47861-transplanting-h6.html
Rolled LLBeans are cheap
