I'm trying to lean out a car that goes through gas like a drunken sailor. To start the process, I want to convert the carbs back to the original factory jetting then address the performance issues if that setting is too lean. Hopefully, there are authorities on carbs out there that know the answers to the following questions:

/6's came with Weber 40IDT3C's, as did the 911T (same engine). The /6 factory manual says the jetting should be:
45 idle jets
105 mains
170 air jets
F1 emulsion tubes

The Pat Braden book on Weber's has the following jetting for 40IDT3C's for the 911T:
50 idles
110 mains
185 airs
F2 emulsion tubes

Which is correct factory jetting for the 914/6?

There are different jetting arrangements for 40IDA3C's. Braden says the IDA's were on the 911L engine. Were they used on other P engines?

There are more references to IDA's in the printed material than IDT's. This doesn't make sense to me if they only came on 911L's because there weren't a lot of them produced vs the 911T's.

What are the differences between the IDA's and IDT's? The external appearance is the same but the jetting is different for engines of the same displacement.

The engine in my car has a 911T crank and case with a 2L 911E pistons, cyls & cams. The 911E was an MFI engine. I've been told there are differences between cams for MFI engines vs carbs. Is this true? If so, how are they different? Should my engine be jetted differently because of it?

and finally, how come a dropped nut will always land in a location that's the most difficult to see, reach, or both? (IMG:style_emoticons/default/idea.gif)

Thanks for the help.