Are the gauges with black background on my TO-30 supposed to have a chrome or black trim?
The original gauges have black backgrounds with white lettering and chrome bezels. They were made by a company that became part of Stewart Warner. Stewart Warner still has gauges that are very close to the original Ferguson gauges. These Stewart Warner gauges are much higher quality than most of the after-market gauges being sold today, but cost more. I can provide you with the name of a company you can purchase them from as well as the Stewart Warner part number for the gauges.
The TO-30 came with an Ammeter and an Oil Pressure gauge. The knockout plug on the left side of the dash was used to mount a Temperature gauge though some owners chose to install an hour meter at this location. Stewart Warner has a temperature gauge that matches the Ammeter and Oil Pressure gauge. Again, I can provide you with the information on that gauge as well.
Ferguson also had a “Tractormeter,” combination tachometer, speedometer and hour meter for the TO-30. Its basically the same as that on the TO-35, F-40, and later tractors. I worked with Steiner Tractor Parts to have that gauge reproduced and it is available today. The gauge comes with the mounting brackets and tachometer drive cable. You will need to purchase the drive unit that goes on the back of the generator.
The generator armature on some of the TO-30 generators was drilled and tapped to accept a drive gear for the drive unit. If your generator armature is not drilled and tapped for the gear it can be done by a machinist. The tap has a special thread and I can provide that information as well.