How much is it worth?

Rather like any antique - it's worth whatever someone is willing to pay for it. It is fully depreciated, and all costs of manufacture, distribution and installation were fully amortized by the first purchaser.

Now, it's an auction market. How badly do you want it? Subjectives are (1) how rare is it, could you find another? (2) How much resource are you willing to spend ($$$, junkyard search time and dirt, etc.) (3) What would you have to give up to allocate the $35 to the tach and not the _________ ?

Can you go out and earn an additional $35? How long would that take?

That's the fun part of eBay - all these @#$% trade-offs and the challenge of being the winning bidder. If the tach is not at a formal auction like eBay, make an offer.

Good Luck,

Bob

:>)