Speedometer cable

Re. 72 Demon - still having trouble with speedometer bouncing. At 65-70 mph it settles down, but bounces before. Some time back a member suggested to trim some off the end of the cable. I trimmed about 1/8th inch off near transmission (4 speed 833) with no improvement. Have been searching for that post with no luck. Cannot remember which end was suggested to trim. If anyone knows let me know. New cable and housing and lubed well. ANY other suggestions would be very welcome.
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