The reason why Mary Wilson appears in a nun's outfit(must be a "habit" she's developed - ha-ha) is due to the fact that Diana and the Supremes had a guest-starring role in an episode of "Tarzan", as nuns.
If you look closely at the front cover (bottom center/right) there is a photo of Mary Wilson in a nuns outfit.....for years I wondered why until now!...John
EMI Britain obviously "farmed out" a lot of its disc-stamping jobs to its Euro divisions. The Motown Chartbusters Vol.7, some of the pressings for that one were done by Electrola, Germany(I have the LP and the CD of that volume) Sleeve by Garrod & Lofthouse, yep, quite the normal, G. & L. did covers for several, if not all the British labels. Wouldn't surprise me if they printed some for Decca as well!