That's why I was suggesting the compression gauge, before you bother to take off the intake manifold. If you've got a head gasket leak, you might be able to tell by the PSI readings. And if you are still getting coolant into your cylinder chambers via an intake leak, you'll see that crap spray out the spark plug holes while cranking for the compression check. If your PSI numbers are all good and close, its a fair presumption the coolant is being introduced via the intake rather than a bad head gasket leak.
Get it otherwise running and get it and the exhaust good and hot. If it's fluid down the exhaust from the original breeching of the intake manifold, get it burned out and call it good. If it's STILL happening, still blowing smoke like that after it sits overnight, you're pulling it back apart again.
You MIGHT be able to see a difference in the plugs you pull for the compression check, if it is a head leak and only getting into one chamber.
And you'll want to change your oil again before you take it on any hard run or road trip. If you got a lot of coolant in your oil it might queer the lubricity enough to wind up with bearing troubles. Check your dipstick after a run for some 'chocolate-milk looking oil. Check the inside of your oil fill cap after it sits overnight (not much use in summer, but if it's chill enough you'll get condensation inside the cap overnight, if there's a lot of coolant in your oil.
One other question - did you drain your coolant system BEFORE you broached your intake manifold? If you didn't, that might account for a lot of coolant making it to your muffler. If you DID drain it down before you pulled your intake, then you likely have a real problem of some sort. And then you start by draining down your coolant and re-opening the intake manifold to see what happened with your gaskets. If anything. After you do a compression check.
Lot of this stuff is basic auto / engine mechanics. If you took on this project you likely know most or all of it already. But I'm putting it in here as much for the audience as for you.
good luck, fingers crossed that it's something minor / silly.