Hi everyone!
So far, with @Pils's CL650_xsaitekpanels.ini file, the multipanel was displaying 0s only, instead of the ALT, VSPEED, HDG, COURSE, etc.
I've been digging into it lately, to try and make those displays work, and I managed to find the datarefs. I now got the HDG showing properly, by using abus/CL650/ARINC429/FDCU-1/words/FCC/0/HDG_SEL.
I have also found the following datarefs for ALT and IAS, but the values are in meters for the ALT, and in meters/second for the IAS:
abus/CL650/ARINC429/FDCU-1/words/FCC/0/ALT_SEL
abus/CL650/ARINC429/L-PFD-1/words/FCC/0/IAS_SEL
For the VS value, I've only found datarefs that have values that I cannot decipher, but certainly don't look like 1000, 2000, 2400, etc; the values are not in feet per minute.
I certainly would appreciate someone pointing me in the right direction for finding those datarefs.
Thanks in advance!