| First you need a punch & hammer so the drill bit will not walk around when you start drilling. You can easily drill & tap the holes with a hand drill. The key is not to drill your final hole size right away. You need to drill a small pilot hole about 3/16" - 1/8". Then you follow up with your final drill size. For example an 1/8" NPT fitting you need a size "R" drill (0.3390"). Just google tap drill size. When you tap you need the right tools. You need a tap handle and some type of oil to provide some lubrication. The hardest part is starting the tap. Sometimes I use a 12 point socket (will accept a square tap socket) with a rachet of your choice to keep the tap square to your hole. Usually after 1-2 turns you can switch back to the tap handle. When tapping you need to rotate the tap back and forth every 1/2 turn to break the chips. Sometimes I take the whole tap out and clean it out completely. Since pipe taps are tapered don't go to deep. Checking your progress with your fitting to see how much deeper you need to go. Generally when you get your fitting just a hair under 1/2 way threaded I would stop so you have some room to properly tighten it down. A bench vice or clamping the manifold to the table will be required. Just take your time and you will do fine. Just make sure you are consistent on the drill angle you choose so keep that in mind when you clamp your workpiece down because you will be stuck in that position for a while so make it as ergonomic as possible.
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