cummins 6BT swap - alternator

[bkvail]

IMG_20170119_223519_846 by Karin Vail, on Flickr

OK, so our 36 Diamond T has a first-gen cummins 6BT (from a 91 Dodge D250).

20170211_164157 by Karin Vail, on Flickr

Hubby keeps saying it needs a '1-wire alternator'. I am the parts/research person (as well as doing a good portion of the wrench turning and grinding/building - the only thing I don't do is the welding. For now, LOL).

Anyhow, so my understanding is - the original alternator is externally regulated? And needs to be internally regulated so that it can charge the battery without the aid of a computer? Do I have that right?

So, I can either go with a 'kit' to make the current alternator internally regulated like this:
http://www.fostertruck.com/alternator-internal-regulator-conversion-kit.html

OR, with a new alternator like this:
https://www.summitracing.com/parts/mci-n13302

Second part to the question:
We have an Autometer tachometer we plan to hook up (D250 did not originally have a tach) - we thought maybe we would go this route to hook it up:
https://youtu.be/HEkgbSxwTVE
I have done a lot of searching and these seems like the best option for us. Any thoughts on this?

 

[Willowbilly3]

An old style mopar regulator can be wired to the alternator. Most Dodge mechanics I am acquainted with know how to do this because it was a cheap fix rather than replace the expensive main processor.
Another thing those engines are common for is a leaking front seal that throws oil all over the alternator. I know this isn't what you asked but before the truck is all put together, it would be a good time to replace if it's leaking at all. It's quite a job and you have to pull the cam to get the inside cover off.