nice work!? I had similar problem - melting insulation from wire used for inductors.?
patiently do the receiver calibration -- please note the re-scaling of the indicator as the receiver gets better.?
perhaps other JA builders of the QCX should check in now -- as you could converse with them on alignment of the rig.? the QCX receiver is wonderful.?
not sure what you mean about best frequency being 6750 kHz -- but please note that exact peaking of C1 may be less important on 40m.? enjoy your rig progress.