Hello I will help you with your question,
The sender is on the driver's side of the distributor at the rear/top of the engine. It is a large cylinder that is mounted at 90 degrees to perpendicular.
Let me know if you have further questions about this
Yes the sender is often the source of the leak at the rear. If you are comfortable seting the timing removing the distributor gives you the needed room to replace the sender.
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