For the non-cutting way of doing this, find an '80/'81 and get the whole underhood harness from a non-electronic BBD model. I wonder if the CARB certified TBI Holley projection would work on the Eagles as well as it did on the CJs?
On the hard starting:
In this pic the 2 small wires on the solenoid are marked "I" for ignition and "S" for start. Hook a voltmeter to the "I" terminal. With the key on, voltage will be the same as at the coil (about 9VDC) When you turn the key to start, the voltage should pop up to 12VDC or whatever the battery voltage is during cranking. If it doesn't, the voltage will drop, which makes the coil's voltage spike drop and plugs don't get enough secondary winding voltage right away to clear off and run.
If the power doesn't spike up, the contact inside the solenoid is worn off.