Each clue has an extra letter.2 down: Ill-natured guy knew about inductance (4) I think it starts with U. 37 down: Many pin up at least ten men (6) ???Y??
Thank you in advance
2: extra letter is (k)new, symbol for self-inductance is L (Lenz), definition is 'ill-natured'
37: extra letter is (p)in, 'up' is an anagram indicator, and the definition is 'at lesat ten men' (in the context of the 'quorum' for a religious service)