FYI ONLY - (Not Meant To Start Debate or Arguments)
The 56 BIRD and 57 BIRD had their own unique brackets as compared to FORD.
1956 BIRD - F/M B6ST 7A185-A
1957 BIRD - F/M B7SZ 7A185-A
1957 FORD - F/M B7AZ 7A185-E
This must have been due to different chassis/body/intake manifold design.
So while different brackets can be made to work, the final calibration of the trans linkage is crucial (non-professional opinion).
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