^^ you can but it requires you to merge the donor harness with that of you cars original harness to maintain functionality of small things like say a gauge cluster....There are also other emissions related items that stay with the car body that now need to be merged with the donor ecu so it can function properly.
Seriously, the wiring if you are comfortable with wiring and know your way around a schematic can take a couple of days. If you are not 100% comfortable with it or your abilities, mistakes are going to happen. Then you get to spend 2 days in a remote gas station parking lot tearing your dash, interior, engine harness out because your car wont run, and you are searching for the one pin in a plug you think you may not have seated all the way into the plug when you merged the harnesses together. This is when it goes good, when it goes bad and you can't even get it started the first time and you need to bring in help to straighten out the mess, start adding $$$.
Simply put it is not as simple as taking the donor ECU and wiring to replace the original stuff with. The two need to be blended together.
These guys are some of the best at the wiring merge, before you attempt this call them, for a price they can do it.
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