On the Plus 4, or at least the LH drive version, there is a cover on top of the footwell over the ECU. It is very close to the ends of the tubes but it may be possible to find something to do the job of draining the water away. The real problem is that if water from the aircon can enter in under the cover so can rain. One way or an other it is a problem that needs to be resolved.

Peter

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