Wow great find
With how his the insignia placement looks like he was with the 508th and final assignment in the 504th hence he is wearing the then current oval and DUI (504TH DUI) on the Ike.
Also him with and his partner at home would suggest current assignment to 508th and then he was assigned to 504 re DUI /oval in Europe??
The picture of him next to mortar sign , could mean he has some connection with 81st Mortar platoon HQ co. 3rd Bn 504th, however i am speculating and could be wrong as it could be an innocent pic??
Stripes on the jacket indicate service time. You could look up his service record through US archives. NH