I see that only 2 film sources are mentioned for this show. I really think there're 3.
Sources 1 and 3 are here referred as being the same source.
http://www.ledzeppelin-database.com/geekbaseweb/sourceinfopage.aspx?sourceid=452
the first screenshot is from source 3, the second from source 1.

I call these sources 1, 2 and 3 from the longest and the most famous to the shortest and less known (because originally misdated).
To sum up :
-Source 1 is the one showed on the second screenshot of the link above, which stops at Trampled Underfoot
-Source 2 is the b&w source mentioned there :
http://www.ledzeppelin-database.com/geekbaseweb/sourceinfopage.aspx?sourceid=453
-Source 3 is the one showed on the first screenshot, and features only Whole Lotta Love.

Why do I think sources 1 and 3 are different :
-they've always been circulating separately, and source 3 has always been given the date of 3/27
-the angle is slightly different
-the circulating source 3 seems to be closer from the master reel
-source 1 features most songs from the first part of the show, until Trampled Underfoot, while source 3 only starts at Whole Lotta Love (1h30 later)

The source that you are calling source 3 (the one that contains WLL) can't be the 27th because Jimmy isn't wearing the right clothes.

Are you saying that it is from the 24th or from the 27th?

Following changes to be reflected in version 1.3

Split First video source for Mar 25th 1975 into 2 sources and adjusted screenshots and lengths
Added newly created source to the boots that contain it