*shudder*
Better than *poop* I suppose. 
If the opposite of *poop* is *dood*, then I think i just did that.
Reasons to think it's gonna be ok;
Topped it up again when cold, did the cap up super tight, took it for a half hour spin and:
1) No coolant leaks/excess pressure (just a gentle hiss as I took the cap off)
2) No excess steam (just a wisp of smoke on this, the coldest and dryest of days...)
3) No emission smells from the expansion tank (just a hot dirty coolant smell....)
Sounds promising huh? Crossing all my fingers...
