I think I know the source, but I'd like other's to chime in.

'92 300SE - small drips of coolant from bottom of A/C compressor - off the mounting bolts and freon hoses.

I've checked the tightness of every hose on the pump, and for signs of leaking from same. Can't see any weepage from water pump, at least at the pulley side.

I'm thinking that it's coming from the attachment point from the pump to the block - or does it attach to the head?

It gravity-leaks - if I clean everything I can find off and wait a couple of days, I get more drippage. I don't smell or see any coolant leaks with the motor at temp, but while driving these small drips will get blown away by air movement.

Suggestions, ideas?