Identify under hood parts

[Rickrey]

Left side inner fender— is this box an electronic regulator? It’s connected to the alternator.
Right side inner fender— I guess this is is a resistor. Connected to ignition coil. Is it necessary? This car has the Allison electronic ignition.

[mbell]

Right side inner fender— I guess this is is a resistor. Connected to ignition coil. Is it necessary?

It's a ballast resistor. Whether it is needed depends on the coil you have and if the car is weird up for a ballast resistor.

Normally you need either a 3 ohm coil or a 1.5 ohm coil plus a 1.5 ohm ballast resistor, giving total of 3 ohms.

Likely you do need it if the car is working well as is. Can check the resistance of the coil to confirm.

[Andy8421]

The Transpo box is a remote regulator for the alternator. I believe it was common on early alternators in the US to use remote voltage regulators. In the UK, the usual alternator conversion for a twincam was a Lucas 17ACR which had the regulator mounted internally.

My guess is that a PO converted to an alternator using whatever was freely available at the time.

[Rickrey]

Thanks !