2001greencrap

Okay, before everyone starts offering opinions about what I should or shouldn't do, even though they will anyways, I am trying to see what difficulties would be encountered when swapping a 1.8t engine from a 1999 5 speed manual quattro B5 A4 into a 2001 2.8 tiptronic quattro B5 A4.

Reasons for doing the swap:
-The 99 has 240,000 miles on the drive train, I bought the car for $400 two years ago, unwisely I might add, with a melted down engine but with a good transmission. I rebuilt the engine because it turned out to be an AEB, got lucky on that one, and drove the car to college.
-The 01 my buddy owns and he would sell it to me for around $300. It has a very nice and well kept leather interior but the previous owner hit a deer and ruined the grill, radiator, core support, hood, and impaired the engine in some capacity but has overall not affected the structural capacity of the car.
-The reason I want to do this swap is because: 1) relatively low cost, 2) I have a shop with all the necessary tools to do it, 3) if I tried to sell the 99 no one would buy it because it looks clapped and the interior is trash although the engine is fresh, and 4) my buddy isn't doing anything with the 01.

- The only thing I am worried about the swap is the engine wiring. I would have to swap to the 1.8t wiring harness and also swap the computer as well. I'm guessing that this will also affect the gauge cluster since the 01 has the digital readout vs the older style in the 99, could i just swap the clusters or would the computer need to be re-flashed? As for the tip-tronic I am not keeping it but also swapping in the manual trans with the 1.8t so I won't have to deal with the tip-tronic's controls. Other than that I have to consider putting in a clutch pedal and swapping the center console for the stick shift.

So I guess I am asking how difficult it would be to swap out wiring harnesses and making all of the electronics still work?