I've found pudles of engine coolant in the footwells and in all of the air vents. I'm assuming that the heater matrix has either sprung a leak or become disconnected.

The manual has a lovely sketch, but it isn't clear where it's actualy located. the car is right hand drive.

It looks like a complex fix involving venting the A/C. is all of that really necessary or can a new one just be plumbed in only draining the engine coolant?

Is there an easy/cheap fix? would a good radiator sealant do the trick? Money is tight and I'm not so skilled!