Anybody know about the 2.3L in a '90 Ranger???

I have an oil leak and I "think" it is the front main seal. The only problem is that there is a bunch of stuff in the way that I am not used to working with, like the crankshaft position sensor. If anyone has had experience with this engine or this leak problem please look at these pictures and let me know if you have any suggestions or warnings for me before I get into real trouble. I want to get the leak fixed so I can give this truck to my daughter when she goes off to college. The engine only has 20k miles on it, and it has always leaked about 2 qts between oil changes from the front of the engine.

Tim