It isn't difficult. A scale of 1 to 10, 1 being topping up the oil and 10 being a clutch change I would put it as a 4.
The problem you will have is age related. The Radiator support at the bottom can corrode and could give issues.
This is how I did mine:
Bumper off, Slam panel off, airbox and pipe out, Fans out.
Drain coolent from Radiator hoses (be carefull, old hoses can split)
Unbolt AC condenser from Radiator
Wiggle old radiator out.
Reverse to assemble
Finally, fill with the correct ratio and colour of coolent, start the engine and bleed the radiator (Bleed screw on the drivers side corner of the rad) top up as necessary. Job done.
I deliberately did mine the long way as it gave me a chance to inspect a lot of the car while it was in pieces.
Alfa GT 3.2 V6 - Daily Driver.
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