Would there have been a replacement for the B61, or was that the B83? The B83 seems rather large and powerful to have been intended as the B61 replacement though.
In the end, had the AGM-131 SRAM II continued development, it would have meant the only gravity-dropped nuclear weapon in the US inventory by 2003 would be a small stock of B53's rated a 9 MT yield and B83's rated at 1.2 MT yield. The AGM-131 would in one fell swoop replace all the B61 nuclear bombs; it would be adopted for the F-15E Strike Eagle, some F-16 units and all Panavia Tornado units.
AGM-131 SRAM-T was not compatible with the F-16, and not only USAF, but Dutch, Belgian, Greek, and Turkish F-16 units were/are nuclear certified. A gravity bomb to replace the B-61 in the tactical role would be necessary.