You can't bore out a 289 to a 302. You can change out the crank and rods, pistons are the same, from a 302 into your 289 block to make a 302. If you’re going to go to all that trouble I would just stroke it to a 331 and be done with it
Without heads and knowing the cam specs, I wouldn’t count on more than 280-290 hp with the info given.
91 LX 337 Incon Twin Turbo
D&D Viper T-56 6 speed
Maximum Motorsports front to rear
88 SSP Secret Service
and it's JUST-N-LX