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Good evening,
In another topic I talked about the oil leaks on my 356cu engine. Besides the rear main bearing leak, I also have a leak from the oil pump. In the manual, before removing the oil pump, the No 1 piston should be 6 degrees before TDC.
Which one is No 1 piston? The one next to the fan, or the one next to the firewall?
Thank you for you assistance.

Front of the engine next to the fan.

The one next to the fan but also make sure it is on the compression stroke and not 180 out. You might pull the cap off the distributor and make sure the rotor is pointing somewhere near 7 or 8 o'clock where the wire for number 1 plug is normally positioned before removing anything. If it is pointing somewhere near 1 or 2 o'clock it is 180 out and the crank needs to make another revolution before you stop it at 6 degrees. There is also a small dot on the pump gear so gently pull the pump so you take note of that position too

It would be quite unusual for an oil pump to leak but the valve covers on the side of the engine above the pump will quite often leak and the oil will run down onto the pump.
You could also check the bolts on the pump to make sure they are all tight before going to the trouble of removing the pump and then having to line it back up with the distributor when re-installing it.