With the glowing endorsements of members who have gone with this one listed on Ebay for $16.06 for a new one we have a pretty decent and economical compromise.
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3 feet of range would put you outside the passenger compartment of the 124 Spider. Lets face it the BT Phone feature is mainly for the driver anyways and do you really want your phone linked up and receiving calls when your further away from the car.
If you want nostalgia you could get the 45 rpm automotive radio with phonograph too but that like an 8 track was impractical. I remember having to keep a spool of splicing and metal sensor tape when you had an 8 Track in a car as heat and cold would take their toll so you had to disassemble the cartridges to replace the splice or metallic track change tape far too often. I am not sure an old school Lear 8 Track would be a good fit with the limited space inside the console of the 124 Spider as I had quite a few of them back in the day and they were huge. A carry case of 8 Track Tapes also took up a lot of space. Could we even fit 4 of them in the glove box with room left for the owners manual and a pair of gloves?