Differance between type S and F ?

[cranky old fart]

I have a '94 K2500 with 176000 miles It is a S type. What are the main differences , pros and cons. I thought I read that if you put a turbo master on a type S you have to keep the vacuum pump to operate the EGR. If you take off the egr does it throw codes unless you swap for a type F computer? Are all 6 lug trucks type S ?
Thanks,Jeff