Harley Shovelhead Voltage Regulator Bracket, 1970-73 (OEM #74533-70A)
Using Bruce Palmer's terminology, there were two "Types" of this regulator bracket.
Type 1: #74533-70
Type 2: #74533-70A
This is a Type 2 bracket, OEM #74533-70A. Like the Type 1 bracket, it is used for mounting the early 4-bolt regulator. And you will note the frame-mounting face has 7 holes, which is correct. Three holes were used for mounting to the frame, and the other four holes were keyed to the kickstand bracket. In contrast, the Type 1 bracket features 5 holes: three for mounting to the frame, and 2 keyed to the kickstand bracket.
Based on the "A" designation, this late version superseded the original, likely due to its increased area over which the kickstand bracket might be applied.