Sir kindly see below point as given in CGST rulesChapter V on ITC
Explanation.- For the purposes of this Chapter,-
(1) the expressions "capital goods" shall include "plant and machinery" as defined in the Explanation to section 17;
(2) for determining the value of an exempt supply as referred to in sub-section (3) of section 17-
(a) the value of land and building shall be taken as the same as adopted for the purpose of paying stamp duty; and
(b) the value of security shall be taken as one per cent. of the sale value of such security.
It is in this context that for reversal purpose the value of exempt supply will be the value of security to be taken as 1% of value of such security sold
a) The issue is with respect to disclosure in the GSTR-1/ and 3B returns at what value should security be shown and under which head of supply ( Non GST supply or exempt supply)
b) similarly interest earned on fds/ bank a/cs whether it is a nil rated supply or exempt (for purpose of discloure in GSTR-1 and 3B ?? )
another interesting point is Security is neither a good nor service so can it be treated as a supply at all.