Most original swap on here, in at least a year..  but a lot of work for 1
or 2 mpg of what might be higher priced fuel.

My wife's 88 vert got 27-28 before I 'turboed' it.

    Don't see why it wouldn't fit.  I would use the trans that comes from a ranger
to make everything easier.
    The biggest problem will be the weight.  Diesels are very heavy.  Pobably close
to a 5.0 V8.  Suspension is not a problem, just swap in the V8 parts.  But You'll
probably have to beef up the motor mount area.
    It would be an expensive project.  You'll have to do the math to see if it's
worth it to you.  In our area, diesel costs more than mid grade gasoline.
    Have you considered a turbocharged 4 from a Merkur?

Have you ever tried to find Mitsu (2.3L TDI) or Perkins (2.2L) diesel
parts for those Rangers?

Can you live with a vehicle that is umpteen times more of a dog, just
for a few mpgs more?

The idea is thoughtful, but being that I own a Ranger and see the
difficuties those with the diesels face when they do break (and they
will), I would recommend dropping in a better cam and porting/polishing
the head on the 2.3L gasser.

The 2.3L Lima flows HORRENDOUSLY, especially if you have the 8 spark
plug head.  Despite that, my Ranger gets mileage close to what a diesel
Ranger gets, if not better, for cheaper cost and better parts
availability.  Do what I suggest and you get better power and fuel
mileage.  Only if that could have been done at the factory, right?