I'll add some detail to John's post, since I remember reading stuff by folks who referred to things and thinking "whaaaat?"
To properly drain everything, there's a block engine drain plug under the engine on the passenger side, near to and recessed up above the hose to the oil pan. Obviously not a gurgling issue, just a drainage detail. You get everything out including fluid pooled at the bottom of the engine block when you remove this.
Also, to make sure the air at the topmost part of the cooling system in the engine block is expelled, it pays to remove a bleed screw above and to the left of the coolant sensor and making sure coolant comes out of it (as you fill - you could obviously remove it to expel any trapped air there if the coolant's already been added). That is located on the metal "backwards-S"-shaped coolant pipe you'll see when you remove the passenger-side engine cover.
(photos courtesy of the late great Yahoo Previa Group archive)
Also here's the opinion of Eric Collins, one of the gurus of the group. FWIW I never did the tilt-the-front-end-up thing.[Source: Yahoo Previa Group Archives - "Previa Coolant Fill Suggestion"]
That's what I do too -- with the front end lifted, I fill the system with distilled water, run the heater on max, hold the revs around 2500 rpm to warm up the engine and get the t-stat to open, then I can usually put another gallon or so of water into the system. Then I drain the radiator and the block, and repeat this about 6-8 times, or until the drain-off looks clear. After that, I know the system is 100% distilled water, and can then add 50% coolant (based on total capacity of the system) to arrive at a perfect 50/50 mix. I let the coolant circulate through the system while the van's still lifted too. Then just top off with more water to the "max" line of the tank once the engine has fully cooled (usually the next morning). Might have to top it off a few more times until everything settles.
FYI, I love to use something called a spill-free funnel - it has an adapter that tightens into the radiator cap opening, and then a deep funnel press-fits to that, so that while running the engine, bubbles coming out don't make splashes all over and expanding coolant doesn't overflow. When you're done, there's a plug-on-a-stick that you insert in the funnel to block the bottom, then you pull it off and drain it elsewhere. No muss, no fuss as the saying goes.