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Okay, so I found the tap all is good.. But I pull the fitting out of the head and there is no way that I can tap it without first drilling it out.. Is that normal.. and if so what size drill do I need to use... This is for the oil lines in the Indy heads.. To put the holley jet in it.. Thanks guys..

Sounds like you have not tapped metal before. Here is a tip, after drilling, chamfer (bevel) the entry. Start the tap straight into the hole (check carefully). When tapping, start by turning the tap 3-5 turns to get it started. Then back out 1 turn to break the chips. Then reverse every 1 turn or if the tap feels hard to turn. This avoids breaking taps, which is really easy with #6, #8. A looser drilled hole is less likely to break a tap, but makes threads with less strength.

3 common types of taps:
1) tapered - long lead (taper) for easier turning, but doesn't reach the bottom of the hole
2) bottoming - very little lead, harder to turn more difficult to start straight, but gets close to the bottom of the hole
3) plug - good compromise of above