... no useful replies yet , just for filler - my '61 Comet had similar battery damage like the acid blood in "Aliens" taking out inner fender and dripping into lower rad support and strut bracket . fortunately the early Comet Rad support and related sheet metal is close dimensionally to early Mustang . Re-Pop available parts for Mustang were modified / fabbd' to fit . You may find available Re-Pop parts for similar year Mustang suitable for repairs. ... added some gusset plates to improve on OEM. . . . .. . . . complete Mustang rad supports and pieces are re-pop'd thru @ '73 (?) https://www.parts123.com/parts123/yb.dll?parta~partsort~1~cadffejk~~20 hav e fun