I stumbled across this thread while looking for something unrelated and was reminded of my own flight logging project. While most of my flight history has been recent enough that I've been able to track down registrations and other flight data on my own (which, admittedly, has been a bit of an adventure being generally based in Canada), I do have a sequence of flights from 2006 where I have a firm grasp of the itineraries (unlike almost everything I've flown prior to 2006!) but not the registrations associated with them. These are those flights:
2006-06-08 WS696 YEG-YWG 0630-0910
2006-06-08 WS94 YWG-YXU 1028-1313
2006-06-13 WS107 YXU-YWG-YXE-YEG 1415-1817
I've been at a loss for how to proceed here since the ACARS data I've been able to find doesn't cover these flights on this timeframe. If you have suggestions or are able to track down this data, please let me know.