Phidget - DirectX configuration

Hey there, - guess the best thing to say is that Phidgets are something new to me. Recently received two 8/8/8 controllers and am trying to get started with them. - Since this is an FS2 Forum - that's the reason for buying the phidgets. Initial Target: to provide more input to Microsoft's FS than an off the shelf Joystick can provide.

Brief History: actually flying but would like to use the software for additional exercise.

Current hardware: Yoke, throttle slider, Rudders w. Brakes (gameport) through a 6 slider (throttles) console (serial) with 8 rotary inputs and additional 32 switches, all with 2 positions - On/Off( mainly 4 post DIP switches). The whole package was sold by jeppesen with their own Sim Software but is no longer Supported (evn though I just bought the soft at an airport 4 weeks ago) - they are very firm about that (controls work great with their soft, but the softhas a lot less to offer than the MS stuff.)

Anyway - I am trying to rearrange the "insides" of the hardware, to utilize it with FS2+. The console is controlled by an older Motorola 68HC series, but from what I can find - it was a one time programming deal, that goes beyond my capabilities.
I am trying to put a new board together, that uses the old cutouts in the enclosure, either with the old or new switches and rotaries and once everything is together - have it recognized as a DirectX or HID device, that can be set up to work with different sim software.

The two big Qs are: how many more Phidgets, how to go about the DirectX or HID recognition ???

As for the number of Phidgets:

need X,Y,Z for Ailerons, Elevator & Rudders = 3 variable Inputs
7 slide potentiometers, 2 rotary for Throttles & brakes = 9 variable Inputs
7 rotaries - for Frequencies = 7 variable Inputs

Total of 19 analogue variables - If I do read the Phidget documentation on the 8/8/8 right - I can only put 3 variables on each board - meaning I would need 7 of the 8/8/8 s to handle the variable Inputs - Did I understand that right ??? ( I grew up in germany, working in FL now, so sometimes I do need a confirmation on my understanding of US english ..)

Well - next Q - if I go to the extent of adding this many phidgets - would be nice if the whole package could be recognized as a DirectX so i can use it as an input device for different programs ? Clues? Leads? Links ? Helppp?

One last Q: read the tutorial about wiring the potentiometers, but would like to re-use the old ones I have, since the dimensions on yours are different. However, the ones currently installed are neither 3 or 2 post kinds - they have 4 posts and are currently connected on # 2 and #3, with voltage varying on # 3 with movement - They are not having a ground - advice ??? where to connect the ground? # 2 is +DC constant in, # 3 is variable out .... The Pots are Alpha B100K s.

big thanks in advance for you help - Arno