Hope it'* the TB gasket. The L27 is a bitch to remove in comparison to the L67. The bracketry is slightly different, since your TB actually mounts at an angle to the upper intake flange.
You'll have to remove the throttle/cruise cable bracket, the crossover heat shield, and a couple other things to get the TB off, but if you do this, consider it a prime opportunity to remove your MAF sensor, and thoroughly clean the TB (off the car). Then put the new gasket on, and go along your merry way.
First though, get an inspection mirror and flashlight in there and try to find the highest point you can detect leaking coolant. It'* critical at this point to determine exactly where it'* coming from. Easier to do in a dark garage, or at night, btw.
If you do have to remove the TB, be warned that the L27 upper intake occasionally has a problem with the threaded anchors that the TB studs mount into. They can spin in the intake flange, and not loosen. I suggest spraying a liberal amount of liquid wrench on the nuts (on the TB side) and the anchors behind the TB flange about an hour or two before attempting to loosen anything.
(I've removed the TB on Jseabert'* 93SSE twice, my SSEi once)