I've been having a problem with the TBucket lately, when I reach about 3000 rpm it starts cutting out. Looked like it's time to change spark plugs, I already had some from last summer. So I installed them at .040" gap, still have the same problem. Took it for a drive just to do a couple of tests concerning the problem, the wife doesn't like it when I get on it hard. Sure enough the problem is still there, then I wondered if it would happen if the engine was NOT under load. Sure enough just holding at about 3000 rpm the problem came back. Got it home and the transmission in park, raised the rpm to 3000 and it did the same thing.
I've never been able to set the rpm limiter, which is done by holding the rpm at 1/2 the set rpm and grounding the gray lead of the distributor for 1-2 seconds. For example if I raise the rpm to 3000 and grounded the gray wire, the limiter would not allow the rpm to go over 6000. So my thought turned to a malfunction of the limiter. So I tried to reset it to 2500/5000 several times, no change. I found some MSD documentation to disable the limiter, but that did not make any difference. At some point the problem started happening at 2000 rpm, not sure if it's something I did.
Don't do what I did, assume that the magnetic pickup coil wires are connected to the 3 pin connector for the distributor. The instructions are abit misleading. I measured at the 3 pin connector red wire to orange wire and got an out-of-range measurement of 13.64 MegaOhms. It should be 400-1300 ohms. At some point I started getting suspicious after I pulled the distributor and started disassembly, but I had already bought a MSD 84661 pickup coil at $30. It became obvious that the pickup wires went to the circuit board.
After getting it apart I desoldered the purple wire to isolate it from the circuit. Then I took a resistance measurement of 600 ohms. Magnetic pickup coil is good, that falls between 400-1300 ohms.
I posted a question on the MSD forum yesterday (7/31/2017), hopefully I will hear something today.
Not sure why, but I got gasoline out of the vacuum diaphragm.