what huh

if you do it this way, you would want to get a parts car. what i said before is just list of things you need. And if you shop around for a parts car you could probably find one very very cheap ($800) one that doesnt have an engine or has been rolled or, im sure you get the picture. Even a whole running one for cheap ($1500) you wouldnt have to do the swap. Just sell the one you have and buy the AWD one

1) yes this has been discussed many time on other site 2) out of any USDM Sti would be easist because of availabilty on parts in the future 3) Ebay, NASIOC, craigslist Some advice: the search button is your best friend for these questions

yeah it would be fun but, well not really fun at all

A new transmission will be required. Along with the new transmission comes the front diff, center diff, and tailshaft. You must also get the corresponding driveline for the transmission (side note here, if you are merely swapping one AWD transmission for another the MT typically shares one driveline between all other MTs and the ATs share another driveline; the STi 6-speed uses an AT driveline). There are many rear diff options, and any of them can be used as long as the final drive matches the final drive of the rear diff of the donor car the transmission came from. Front axles should be interchangeable, but newer axles are thicker. CV strength has remained the same and are not a weak point. Rear open diffs can be found on most Subaru models. Rear LSD s came on some Legacy Turbos, Some SVXs, 2000-2001 2.5RSs, and 2002+ WRXs. While final drive ratios vary, the axle splines do not. Your diff choice governs which rear axles are to be used. You will either need rear axles from an open diff Legacy or GC/GF/GM Impreza for an open diff or rear LSD axles from a 2000-2001 Impreza 2.5RS (ask for axles from 05/2000+ to be safe) for a rear LSD. If you are converting from AT to MT or viceversa, you will need the corresponding ECU since the AT ECU expects a TCU signal. You can trick it as some have done. Along with the basic driveline components, you are going to need most of the rear suspension and mounts from the transmission back. This includes the transmission crossmember, rear diff crossmember (and all in between), AWD gastank with driveline hump, struts and springs, AWD knuckles, a plethora of bushings, with the possibility of lateral links, swaybar, and trailing arms also being needed. Your best bet is to find an entire donor car that can be stripped. If that is not an option, you will be, as beachbum has said, 'nickle-and-dimed to death'.

you might be able to find some this guy http://medford.craigslist.org/pts/979755765.html