Salve caput - how to distinguish translations?

I'm working on adding the hymns to HTP1971, the Plymouth Brethren hymnal Hymns of Truth and Praise. Hymn no. 131 in that book is a version of the Latin hymn Salve caput cruentatum, generally attributed to Bernard of Clairvaux, and usually brought into English via Paul Gerhardt's German version beginning "O Haupt, voll Blut und Wunden". The first line of HTP1971/131 goes "O Head, once filled with bruises," and the translator is said to be James W. Alexander "(alt.)". Much more common first lines for cognate texts are "O Sacred Head now wounded", "O sacred Head, sore wounded", and "O sacred Head, surrounded", each of which is also often said to have been translated by Alexander. Some versions are said to have been translated by Robert Bridges, or to be a melding of translations by these two gentlemen.

When I search the database for "O Head once filled with bruises", in an effort to determine what text authority to use (or whether to create a new one), I find the result is O Head, so full of bruises, so full of pain and scorn, with 16 instances and in many of those cases listing one John Gambold as author (not translator), usually listing the DNAH hodgepodge "O head, so [once] full [filled] of bruises, So full of [oppressed with] pain" as first line. On the other hand, if I search for "O sacred head sore wounded" the results show three text authorities:

(1) http://www.hymnary.org/text/o_sacred_head_now_wounded (O sacred head, sore wounded - 609 instances),
(2) http://www.hymnary.org/text/o_sacred_head_sore_wounded (O sacred head, sore wounded - 18 instances),
(3) http://www.hymnary.org/text/o_sacred_head_surrounded (O Sacred Head now [once] [sore] wounded [surrounded] - 60 instances).

All three versions at least in some instances cite Alexander as (a) translator. The third ("surrounded") is generally ascribed to Bridges.

My guess is that all of the above versions (except the Latin and German) should be under a single text authority, and there should be some detailed explanation in "Additional information" about the various translators, if possible giving the original translations of each. If I am duplicating an earlier post of mine here, I apologize.

o_head_so_full_of_bruises_brow_that_its is another text that is in a few cases confused with the "Gambold" version. I'm trying to weed those out as I meet them. There was also a problem with an inversion of order of hymns #27 and #28 in HPBU1795; I think I have fixed that, or will in a moment here.