I've got an NH carb, with an offset drain. I've bought, a bunch of parts, for a rebuild, but the plug, that holds the bowl on, doesn't seem long enough. If I put it together, with the gaskets, the plug wont catch. If I put it together, without, the gaskets, it will catch, but will certainly leak. Any tips?

That sounds like the NH that was on my touring when I bought the car. The carb was leaking fuel, and when I took it apart I found that it was badly rusted. With the rust removed, there wasn't enough of the threads left to hold the plug. I took the coward's way out and paid $20 for another NH at a swap meet, and rebuilt that one. There may be some way to salvage that body, but it may be easier to find another one.

Is it feasable, to drill it out, and repair it with a heli-coil, then use a short bolt, instaed of the brass plug?

I wonder if that float bowl is from a Kingston L4? They have an offset drain but are deeper than the correct bowl for an NH.

NH carbs had an offset drain valve on the earliest straight thru version. That bowl is not the same as the bowl for an L4 Kingston.

The bowl should be close to touching the bottom of the main jet protrusion if it is for an NH.

I considered a helicoil, but none was available in the right size.

Royce, The bowl, is just short of the main jet protrusion. About the thickness of the gasket. The carb is a 1920-22 style, so the bowl is correct for the carb.

Steve, I realize that the threads would be different. Thats why, I thought the Heli-coil & a normal bolt. Would I be doing something good, or would a repair, of this nature, be sacrilegious?

Here's my vote:
1. Find a good core (already suggested and seems the most logical). There are probably 100s of them laying around these guys garages.
2. Find one of the center drain valves from one of the vendors or some other t'er near by and see if that will thread in and hold. The center drains were about a 1/4" longer and may reach some unused threads.

You could take the sacreligious route. Your only gambling your T if it doesn't work and leaks gasoline while your driving or parked in the garage.