Too cloudy here, so didn't have a go this evening.
A few points on what's been said above. Trying to meter and setup in advance of the pass is difficult, the light changes so quickly for me here.. making it something of a guessing game. The final few minutes before it is due to arrive on your western horizon are key.
On a long pass shooting into a sun that has only recently set can be very bright. I've some time stopped mid way through the pass run to the bottom of the garden and shot it flying east into the shadow - always a better photo.
The wider you shoot, the less of an issue start trails are. Likewise, if you're shooting in closer with a zoom and you're pointing towards north you can minimise the star trails also.
I shoot ISO 100/200 most of the time as I find (my camera at least) to be pretty noisy on low light high speed shots.
I've never tried stacking any images - I'd be interested to see how they looked. If you could do the whole 'subtracting dark flat' thing it might make for a special image.
I've tried shots with all manner of options as there are so many variables. As wide an aperture as you can manage when the light is low, obviously and keep an eye on it when it's at right angles to you and moving away... I (one time) managed to snap a few hopelessly blurry pixels but it's just about enough of a suggestion of the actual shape of it and the solar panels sticking out.
300mm, f 5.6, 2.5 seconds, ISO 200