Hi Jesse
You might be aware that
depending on your budget and your requirements
for diagnosis you might also go for one of the pre-made diagnostic OBD I+II devices
built by Foxwell or Actron or others.
I once had an Actron CP9145 code scanner
(together with the CP9127 ALDL Cable Kit)
and it worked flawlessly also for my 1993 3.8L
(now sadly dead despite of all the diagnosis ;-).
This stuff appears on Ebay.com etc quite often.
The one mentioned is now replaced by the current and fancier Actron CP9690's it seems
(but I have no experience with these).
The advantage is
you do not need to schlep one of these vintage laptop computers (with serial interface)
that are quite shaky sometimes in themselves (namely the batteries).
Disadvantage is
Actron + Co are somehow inferior in functionality -- e.g. the software for the laptop+interface gives you a much better view on live data from the system. Really expert!
But for just reading and clearing error codes these devices are totally fine.
As you are looking for nowadays exotic stuff you might have to do quite some research one way or the other.
And welcome on board of the forum!
There are mighty helpful people around here.
If somebody here has better ideas or wants to make an offer but does not want to answer in English you can send me an PM and I will try to translate to the best of my abilities. :-)
Concerning the interface
Carsten (said fronrath) recently wrote
that interfaces still get produced sometimes "but only when it rains" ;-))))
http://www.pontiac-trans-sport.de/showth...20#pid8220
3.8 transports and use 1 of these as dialy driver, just passing 395000km 
been all over europe with this one on vacation trips and want buy a interface to diagnose. it's a - 93 3.8, is there anyone intrested in selling one to Sweden?