oil pressure

I'm reassembling a 350 and need to know what goes in these oil pressure holes? There's one above the oil filter and one next to the distributor. Do I need both?

I have a 5.7 350 doctored up to a 383, 9:1 compression and I was wondering what you are using for an oil pressure sending unit and a starter. The block is an 880 casting, vortek heads, and I will be using TCI headers. The area for my sending unit is pretty small and to the rear of the...