I was looking through the Off-Road Adventures website and found this article (http://www.oramagazine.com/pastIssues/0409-issue/040918d-oldiron.html).
This website is owned by the 4 Wheel Parts parts store chain but please don't take this as spam! It just contains a lost of info and I thought it might be helpful to have.

Good info, thanx for posting that link.
Dano

Interesting... I see an error though:

1993
A more powerful HO 200 hp version of the 4.3 L becomes optional. The 160 hp version remains standard.


The CPI 4.3L was actually introduced in 1992... I have an 1992 Blazer with it. ;)

Good stuff thanks for the link