Non-invasive switch repair for Classic?

[John R]

I recently acquired an HP-70 (finally!) that is in absolutely beautiful cosmetic condition, but that unfortunately exhibits some on/off switch flakiness common to vintage Classics. In particular, although the switch feels solid, gentle rocking of the switch in the "ON" position produces various kinds of aberrant behavior, ranging from illumination of random display segments to alteration of the display format (i.e., what would normally be achieved using the DSP key).

I am wondering: has anybody ever heard of any non-invasive repair or "therapy" to fix or mitigate this problem on a Classic? In the past I have opened up Classics to fix this sort of problem, but I've never gotten the back label to look as nice as it did before I started. Given the beautiful condition of this calculator -- and the rarity of the HP-70 -- I am reluctant to pursue such a solution here. Any advice would be much appreciated!