About the size of a small glass, be prepare!!!! when you remove the old one
to get some in your face (he he he), the O-ring is the problem, put some WD-
40 to help get this one in faster, it will go in easier.

After it's done and your all wet!!! Start the van and open the thermostat
bleeder screw, but this is not a must at all, just open this one as a
precaution.

Have fun, Ben (i did that many time when i was testing 3 new thermostat and
temp sender, at the end i was not even openning the bleeder)
http://www3.sympatico.ca/huotx/engine1.htm