Here is a little arpeggio progression using: A7 G7 A7 C7 D7
Stream: https://soundcloud.com/missingsomethin/a7-g7-c7-d7-backing-track
Download MP3 here: https://www.dropbox.com/sh/zbm3hswbge2tvvm/v3656OkGlJ

I thought I would give it a closer look.
Just picking the key of A (since I start with that chord?) I have the following:
A7: 1 5 -7
G7: -7 4 -6
C7: -3 -7 -2
D7: 4 1 -3

In choosing a lead scale/mode, do I ignore the C7 D7 as a "passing tone" since it's shorter and connects back to the main riff of A G A?
Otherwise, that -6 in the G7, and the -2 in the C7? This would make it -3 -6 -7 for a Phrygian mode (-2 -3 -6 -7)
Before any of this, I tried to just play some lead licks by feel, and then looked up the chosen notes, after the fact.
And these are the notes I gravitated towards naturally, anyway.

Can anyone loop it and post a recording of their own leads over it?
I will do the same. I am curious how different people interpret leads over the same progression.
1978 Les Paul Custom Sunburst
2001 USA Strat (Hot & Cool Rails)
Effects: Boss GT-6 with Tech-21 Power Amp
Without actually trying it I would suggest that looking for a single scale to solo over such a progression is probably the wrong way to go about it. Following the changes it probably a much better idea.
R.I.P. My Signature. Lost to us in the great Signature Massacre of 2014.

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