What size engine do you have? If it is the 4.6 V8, the sparkplugs will be right on top of the engine, and each plug will have it's own coil. This engine should have a 100,000 mi tuneup interval. This is where the owners manual will come in handy as to telling you about scheduled maintenance. From what I have seen, the fuel rail and injectors will have to be removed because they are up over the coils, and blocking their removal. Also, half the engine is up underneath the firewall. Good Luck.
The engine oil dipstick is on the drivers side of the 4.0 liter V6 engine in your 1999 Ford Ranger Helpfull
On your 1992 Ford Ranger , 4.0 liter : The starter should be on the drivers side of the engine , low down , where the transmission bolts to the rear of the engine
On My 93 pickup it , you have to remove the battey and its is just inside the fender. Rick
Underneath, drivers side, inside frame rail, aprox under drivers seat.
On a Ford Ranger with the 3.0 liter " Vulcan " V6 engine : The engine oil filter is on the drivers side of the engine
You will have to remove starter, It is behind the starter in the block.
On a 1999 Ford Ranger , 4.0 liter V6 engine : The engine oil dipstick is on the drivers side of the engine
I believe it is on the valve cover , drivers side of engine , towards the rear
On a Ford Ranger , 3.0 liter V6 engine : The engine oil filter is on the drivers side of the engine
Remove the oil pan for access
I know on the 4.0 liter V6 the lower radiator hose connects to the water pump
On the (4.0 liter V6) it is on the drivers side of the engine below the power steering pump