Nice looking truck! I used to have a real similar one. Whether or not the PCM needs the oil pressure sensor depends on what year your engine is, but I'm going to assume its a GenIII since you didn't mention otherwise, so if that's the case you don't need it. To install the DD sender you can either tap the bypass block above the oil filter or you will need an adapter to put it in the stock location. Be careful with aftermarket adapters because they are usually pretty thin and will snap off easily, seen it done several times. Or, you can do what I do and break off the plastic part of the original sender and drill and tap it for your sender. Super easy, cheap and wont break like the aftermarket adapters. There are pics in my thread in post #26.
https://ls1tech.com/forums/conversio...-c-10-a-2.html