The pump and bracket pictured appears to be a Saginaw style pump from a 383/440. Additionally the 1973 power box is going to give you problems as the 1973 has a 1-1/4" Pitman shaft and your 1966 would have a 1-1/8" Pitman shaft.
The pump and bracket pictured appears to be a Saginaw style pump from a 383/440. Additionally the 1973 power box is going to give you problems as the 1973 has a 1-1/4" Pitman shaft and your 1966 would have a 1-1/8" Pitman shaft.