Clarification on Orientation of Charge in Crest/Coat of Arms

Hi,
I'm hoping to have a family crest/coat of arms adorned to a gift for my family, who's a geneaology buff, however I'm unsure of the correct design.

Namely, I've been leafing through some files and search results to clarify the orientation of an eagle's leg in the design of the crest.

One of our ancestors drew it as "claws to chief" in the mid-1800s however this doesn't align with the description in "Fairbairn's book of crests of the families of Great Britain and Ireland" (if I'm reading it correctly) nor tradition, which I believe implies it should be "foot to base" (as the eagle is a bird rather than a beast).

Any help would be tremendously appreciated.

Excerpt from Fairbairn's: "Robert  Jocelyn.  of  Castle  Waller, co.  Tipperary,  Ireland,  out  of  a  ducal coronet  or,  an  eagle's  leg  and  thigh erect  gu.,  in  front  of  a  plume  of  five ostrich-feathers,  alternately  arg.  and az. Honor  et  Veritas"

Images below:

https://preview.redd.it/k4z0p6uhtzva1.jpg?width=300&format=pjpg&auto=webp&s=6629e5903fa929ebd2eb608c56cf11ae12d9c761

https://preview.redd.it/ua6d4auhtzva1.jpg?width=3024&format=pjpg&auto=webp&s=caca059e97b4b74e308fb65e4e70d0bbff8bd572