How about a context sensitive glossary, which underlines words (like arb, and carb, etc...) with some help text like a description or the unabbreviated meaning (so for arb - Anti Roll Bar - Suspention Component) when you hover your mouse over it.
Installed - but I don't know what words you want done... post ideas below, currently just FIAT done - and before people complain it looks dodgy, I know - I've already requested a feature where the box is only as wide as the text - so expect that soon.
(You can do just words to popup words, or words which popup to a link - so a link to Wiki or something...)
Oh and to disable it, go into the control panel > options (it's at the bottom)
I don't know if it may even be a good idea to enter stuff like cam and sump, a cam being an offcentered doo-dar and a sump being that thing where all the oil lives
Oh another acronym - ECU - Electronic Control Unit (NOT ENGINE control unit) - EDIT <- that looks like I may have been having a dig at helcat, who also put the same thing, and was also correct
Hmm... Wiki disagrees with you on the ECU front there... whilst there are a number of Electronic CU's in the car, it refers to the main one we all know as the Engine Control Unit....