UPDATE 1 — India's Tata Group stocks fall after SP Group unveils $2.6 billion stake sale plan
(Adds details throughout) Sept 18 (Reuters) — Shares of most Tata Group stocks fell on Friday, a day after Shapoorji Pallonji Group proposed selling a portion of its stake in holding company Tata Sons for at least 250 billion rupees ($2.61 billion). As of 9:40 a.m. IST, Tata Chemicals tumbled as much as 7.8%, while Tat