** Smithson Investment Trust's shares SSON.L up 6.8% at 1632p - milestone such as top gainer on FTSE Mid 250 Index .FTMC
** SSON is converting its assets into Smithson Equity Fund, a soon-to-be-established open-ended fund
** Co said shareholders opting out can redeem their holdings at NAV
** Fundsmith, SSON's investment manager, will cover part of the restructuring costs to ensure no NAV dilution for shareholders
**YTD, SSON stock has risen 9.71%
(Reporting by Tuhina in Bengaluru)
((Tuhina@thomsonreuters.com))