Well, this is where it gets kind of tricky. See, I read a short excerpt at erowid (no doubt we read the same thing) that said to do just what you are saying. Well, I didn't read it so much as I skimmed it. Maybe I should go read it to see if they cover what I am about to say more thoroughly. In any regard, non-polar solvents should be what are used to extract the amides derived from d-LSA. These amides are similar to d-LSD but there is, in fact, no LSD in morning glory seeds. The amides are bases. The carboxylic acid d-LSA is an acid. So polar solvents are well suited for extracting this compound and others like this one. There are a great number of lysergic acid derivatives in these seeds, not just simply one thing or another. So this is reasonable to use non-polar solvent to remove the amides first and then extract with a polar solvent.
I need to go back and read the article but if I remember they used some HCl(aq) in the extraction? This would be a mistake in my estimation. There is a reason why ergopeptide salts are not the ever typical hydrochloride salts. Ergopeptides are a class of compounds that include LSD, ergotamine, ergometrine, ect. The d-LSA itself is not an ergopeptide. Anyway, ergotamine tartrate, d-lysergic acid diethylamine tartrate and so on are such because the hydrochlorid salt tends to degrade the product. I know not if the problem is that these compounds degrade back to d-LSA or if some other part of the molecule is affected. I suppose it'd help if I read the article at erowid. Is this the one?
Erowid Morning Glory Vaults : Extraction of LSA (Method #1)
In any regard, if the amide does not do well with hydrogen halides like hydrochloric acid, hydrobromic acid and so on then it would be okay to use HCl(aq) to extract d-LSA as it is not yet an amide. If it is some other part of the molecule then these acids should be avoided. It is this reason that dilute H2SO4 is used in the acid/base extraction utilized in d-LSD syntheses.
Don't worry, I am sure your knowledge of chemistry is fine. There is just a lot to learn. College courses are certainly a good place to start ;-)!
Moriarty