Yet another alternator question...

[a175]

Is it safe/normal for a stock (ish) M1008 to be able to start and operate with only one alternator mounted? What issues (other than battery drainage) could arise from continuing to operate the vehicle in this manner?
Also, how the heck is this even possible?

 

[Warthog]

If you are going to only have one installed make sure it is the driver side. The passenger side charges the rear battery only comes into play while starting.

I have run a truck without either alternator. Not recommended but can be done.

Is there a reason you only want to run one alternator?

 

[a175]

Not so much wanting to... just that's how it is.
The truck sat at my folks' house for awhile when I was away, and now that I have it back I'm slowly getting it back together. Runs and drives well enough. Needs a new steering gear box and hydro boost (per mechanic's diagnosis, and I consider him trustworthy). I know the passenger alternator died a few years back, and apparently it's M.I.A. I remember taking it off, don't remember how I got it set up to just crank and run with a single alternator.
GEN 1 light stays on. Voltage never gets past middle yellow.