Better Sino-Indian relations in the 60s can change politics in both countries to the extent that global politics is unrecognizable by 1990s. Have the Pakistanis be supported by the West or the Soviets earlier, and the Chinese will support India instead. Good relations between China and the USA might be butterflied away altogether, as will the Good relations between USSR and India. NAM might hold a lot of weight in this TL.
Just make India a little bit more aggressive/assertive wrt Pakistan to the extent that the west backs the pakis as early as '48, while at the same timem showing China that the Indians aren't pushovers-- and would instead make a good ally.