no reason it is impossible...I have seen this discussed several times...basically the conclusion is - COST-WISE, it is cheaper to just replace non-nav with a nav. trade in for a new or used one whatever.
Now on the technical side - like Noel said - it is a BIG job - I'd call it a messy job too. with NO WARRANTY.
Now on the technical side - like Noel said - it is a BIG job - I'd call it a messy job too. with NO WARRANTY.