Refer to either of these

Note: the GM alternator WILL fit into the old Prestolite bracket, however it will be too far towards the cowl for the belt to line up and the lower height doesn't allow for the belt to be adjustable. What has to be done, is to heighten the mounting point about 2 inches above the existing spot. Sooooo....

An old Generator bracket will fit any stude engine. Find one or make a bracket and use the holes in the Prestolite as a template to drill new ones. The generator bracket usually has a high tab, but it was the end used by the rear of the generator. You have to swap ends to use the high tab forward. This leaves drilling new mounting holes, so the mount aligns with the belt pullies. you also have to enlarge the tab hole to 3/8" for the Delco mount bolt.

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