need some advice

after i get all the crap thats messed up fixed i want to either soup up the 4.3 or drop in a lt1...my delima is the 4.3 has 155,000 miles on it and im not sure if it would be worth it ...from what i understand to drop a lt1 in would cost me about 6 grand including cost of the engine..could i get that 285 hp out of the 4.3 for less and if so would it be worth it with all the miles it has on it ...oh yeah its a 97 4x4