Let's not get the cart in front of the horse. There is no need to replace the evaporator unless it is diagnosed as having a leak. Even though the ones in the 124 cars are prone to leak, they are not DESTINED to leak. Mine is an '88 model and still doesn't leak (knock on wood.)

Doing a/c work involves MUCH more than just laying out some money for the necessary tools and equipment. You need to read and study thoroughly not only the concepts, but the diagnostic and service procedures. I've been around automotive a/c service since I was seven years old and that was almost 50 years ago. My Dad started doing auto a/c work in 1956 or 1957.

I am always one to encourage DIY, but in the case of a/c service you not only need to look before you leap, but study hard before you leap.

BTW, if you have a bad hose, you can go to any a/c shop and they can replace the rubber part of the hose using your fittings. All you have to do is take them the hose. It's not very expensive to have a hose redone. New hoses are EXPEN$IVE!

Good luck,