Boil for 5-6 minutes. Remove gourds, drain and wipe dry. Heat half oil, in a pan, add crushed seeds, and take off fire. Add all other masalas, salt and mango powder or gratings. Cool gourds and masala before stuffing.
Press slits to compress.
Place gourds in a glass jar. Heat and pour remaining oil over them. Cool, cover and keep aside. Shake lightly once a day, till the gourds are tender and pickled.