Here is another source for info and parts -
https://www.carburetor-blog.com/article-categories/holley-4000/20Hg
steady indicates a healthy engine (IMO).
Maybe make sure the primary throttle blades are not hanging on the intake carb pad bores and/or carb mounting gasket, the throttle shaft bushings are tight and the throttle blades are aligned correctly and not bent (some one else may have been in it).
Is the choke cross-over tube still connected and functional? Follow the curb idle procedure outlined in the WSM exactly.
Listen to TED and let the board know what you find as this will be helpful to others.
[U]FORGOT - CRS ...
Make sure the CHOKE ASSY is fully functional and the FAST IDLE CAM drops fully before setting curb idle.
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