Air Con Evaporator replacement

Hi I am based in South Africa and summer has arrived with a vengence Eleventh day of spring and temperatures of 39 degrees celcious allready. And yes you might know my air con has packed up.
I have been told By an Air con Expert that I need to change my evaporator .
He says after supposedly fixing a leak and regassing the system three weeks ago and adding a dye, that if the gas has now again leaked out and dye is seen inside of Air Con drain pipe then the evaporator is the problem. And it needs to be replaced.
Can this be done without stripping the entire dash?
I have seen a post saying that you can replace the evaporator via the passenger side footwell and glove compartment with minimum stripping.
Can anyone point me at any members repair posts that cover this procedure.
Also reading the main discussion postings; it would appear that the potential for losing gas as my car has done can be because of other leaks on the system and may not even be the evaporator.
I am terrified that the Air con people here some of them (not exactly experts) are going to be able to srip and rebuild dash without messing up the car permanantly and any pictures guidence notes and things to look out for would help tremendously.