dead speedometer 1976 tr-6

[s7101 <s7101@jane.penn.com>]

it just died--only sign of ill health was a jumping needle, that i was
willing to live with.  should i assume it is a cable?  there are two
cables one to a service box the other from the service box to the
trans.  would appreciate guidence in diagnosis of problem==hate to
replace more than what is necessary.thanking you in advance steve volpe
Pa.