One more item that needs to take a look at is, the long plastic coolant pipes that go to the the front from the rear.  They tend to have their ends break off and the insert to slide out.  One can feel them through the hoses by just touching it there.  
Need to take the hose off, take that broken end out of the hose, heat up the end of the pipe a little with a hair dryer or a heat gun, hammer the insert back into the pipe, drill two little hole on the side about half inch from the end of the plastic and screw in a flat headed screw there to hold the insert from sliding out, now you can slide the hose over the screws and tighten the hose clamp.  Done.  
The two pipes have four ends, of course.  Fix them all and you'll have no surprises by suddenly loosing all the coolant at the traffic light.
If you have not lost much coolant in the repair process, you don't need to worry if you have an '86 and newer system.  The older ones need to be bled properly though.  
And while you are under the car doing this, it is only fitting to change the T pieces of the heater hoses too, I guess.

Enjoy having your van,
Zoltan