water 6 has too low Ca; most of the others (except 2) have high HCO3 (typically you would want less than 125ppm, except in darker beers)
if I had these options and only had MgSO4, I would:
take 10 qts of water 2 and 5 qts of distilled/RO water and strike with that. add 3.5g of MgSO4 after you add the grains.... should take the chemistry to Ca:53, Mg:33, Na:3, SO4:103, Cl:113, HCO3:7
fill the HLT with the necessary amount of water for sparging to attain preboil volume; use the same ratio (2 parts water 2, 1 part distilled/RO)
if your preboil volume is 7 gals, then you need another salt addition for the makeup water (7gals - 15 qts [14.2L] = 13 qts [12.3L])... using the nomograph to hit the same numbers, add 3.0g to the boil to get similar water chemistry as the strike water.
the SO4:Cl ratio wont be hop dominate; it will be mildly malt dominate to balanced. the Ca is high enough not to cause problems; the HCO3 is sufficient; the Mg shouldnt be high enough to cause any gastrointestinal disasters...
hopefully, this helps
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