Worth checking. Known problem with wiring harness.

wiring had rubbed on left frame rail where plastic splash guard covers the end of the transmission, repaired transmission worked perfectly - before repair you would swear it was burnt up

548 cu. in., Bill Mitchell Aluminum Block, CRT 727 auto trans, Alston Chassis. 8.981et at 149.46 mph. 1.204et - 60 foot, So Far....