I don't know if it's an issue but here's what I experienced. I built my Model 4 light (I thought), all speedster except for the long wing. It's a tail dragger with Grove gear, 912ul and basic panel with a lightweight Becker comm and no transponder. I first weighed it with 3 sets of bathroom scales. then my A&P buddy offered to weigh it with his aircraft scales. They're "high end" aviation, certified, digital scales that calculate CG. Anyway, I'm sure they're more accurate than my "cheapo" bathroom scales. Guess what! It gained 40 or 50 pounds. My Model 4 is heavier than your 7. So you see why I have some doubts about your empty weight. Could be and I hope it's right. Either way, good luck with yours. James Thomas