According to my research you don't necessarily HAVE to pull the engine, but you will have to remove the timing belt components to gain access to the oil pump, which could be time consuming and extensive due to the location. If you don't have a Haynes Repair Manual, I suggest investing in one because they have all the necessarily steps outlined for this procedure.
Replace push-rod
it is internal to the pcm (engine computer)
behind the glove box
You can get a diagram for your 2000 Dodge Caravan rear door hatch handle and most Dodge dealerships. Your local library will have Dodge service manuals with the diagram.
5w30 or 10w30
Need to replace rear spark plugs
Engine idling in park.
The 2000 Dodge Caravan oil sending unit is located on the bottom of the engine. It is on the front on a six cylinder, and the rear on a four cylinder.
Yes.
5 quarts
You unbolt the old one (one bolt) then fit new. Now refit the belt.
On a 2000 Dodge Caravan, the wiper motor is located under the hood on the passenger side of the engine compartment. It is found over the strut tower in the firewall.