<p>Aaah... just discovered that the seal on my "soldapult" has decomposed, so it doesn't draw a vacuum anymore.  So I am definitely going to try the piggyback approach.  </p>
<p>I'm fairly good at this sort of thing -- I've built ugly-style RF circuitry soldered onto unetched copper PC board, and I like the physical challenge of making good mechanical joints before soldering.
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