desert whomper

i got home this morning from down below with my mom and when we pulled up i saw a puddle under my truck, great i thought. i pop the hood and i see coolant leaking from somewhere by the throttle body/upper rad. hose. I could see it just dripping and i havent driven it since the night before so why would it leak all of the sudden and not while im driving it? I just replaced both radiator hoses and the intake has all new felpro gaskets.

88w/300K!!!

I had the exact same thing with my '88 22RE. I figured it was a head gasket gone bad. Didn't have any oil/water mixing problems going on, so I just added some Prestone Stop Leak to hold me over until I do a complete engine rebuild or replacement.
I think it leaks while not running because just sun light warming up the car expands the cooling fluid enough to send it out the leaky spot. Could be wrong, but in my case the Stop Leak did the trick for now.