[tubman]

The stock Mercury manifold and a small base 2G are about a good a match as you will find. It's almost serendipitous. Run the carb backwards and everything fits into place if you run an automatic choke. The only thing that needs to be "matched" is the choke linkage. Both the Merc and 2G come in "regular" (choke mechanism on the carb) and "divorced" (choke mechanism on the manifold) configurations. Match the carb type to the manifold and hooking them up is as simple as bending a rod (former) or shortening the heat tube (latter). As stated, the manifold should be bored out to match the carb (1 7/16"). I use a cutter called a "Rotabroach" and an old 2G base as a guide and do it on my drill press. One word of warning : 2G's have voids cast in the base for exhaust heat purposes. These voids are very close to the edge of the Merc mounting surface and can cause vacuum leaks. I made 1/4" aluminum plates that go beneath the carburetor to solve this problem.

If you would really like "some reliability", I would avoid an electronic ignition like the plague. While the car manufacturers have them down well, the aftermarket units not so much. Throw in 6 volts and the "dirty power" supplied by a generator/regulator system and sudden unexpected failures enter the equation. Because of their very nature, points ignitions fail over time and the signs are unmistakable. Keep your ignition system maintained properly with quality parts and "points will get you home". It's also a lot easier and cheaper to carry a set of points and a condenser than a complete distributor or even a module.

I have had this setup (a 2GC and a Mallory dual point distributor) on the '51 Merc in my '51 coupe since I installed the engine in 2016. It failed just one time and that was my fault as I was testing my 6 to 12 volt "Tach Driver" at the time. The "modern electronics" in the prototype failed and killed the points ignition. When I disconnected the device, everything was fine again.

New isn't always better.