With the rear of the plane almost completed, except a small part needs to be sheeted +covering, I went ahead to balance the plane (with landing gear retracted).
Didn't use any balsa blocks in the tail to reduce weight, but it still needs 980 grams (>2 lb.) in the nose.
Motor and prop are installed, so the additional weight needs to come from battery and cowl. I had settled for a 200g. motor and around 400g. battery.
But in order to reach the necessary "balast" I will have to go for a 400g. motor and 800g. battery (2x 3S 400g.)
Making the AUW around 3.2 kg. ( 7 lb. )
It would probably fly OK, but that means I have failed in my attempt to build a lightweight electric version.