1. need a photo from further back, but if it's over near the battery it's probably a leaking heater valve.
2. There is an o-ring. I assume this is the pipe held to the water pump with a single 10mm bolt?
3. this (kick down on hard throttle) isn't the function of the modulator, that is the function of the tv (throttle valve) cable, which is the cable that hook of to the throttle and goes to the right side of the transmission. The vacuum modulator controls how hard or sodt the shifts are.

Gilly

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