At Dave's suggestion I have started to build a Weight & Balance spreadsheet. It's just over 100 lines long so far with each component listed along with estimated weights and individual c.g. locations. As I have the final parts I am replacing the estimates with actual weights.
The biggest uncertainty right now is in the weight of the main fuselage sections. My WAG entries for those total almost 20lb, but I feel that I can significantly improve on those weights.
The overall good news is that I'm tracking to my original 50lb dry target, and it is currently looking like I will need around 1lb of nose ballast. I'm sure the c.g. will follow the habit of racing towards the tail as time progresses........
I'm using the full-scale c.g. range from the maintenance manual, which gives me a 36mm spread (1294-1330mm from the tip of radome). I will double check the location and maybe make a foam chuck-glider as a further validation that the c.g. is in the approximately correct location.
Paul