vortec changeover

i have a 93 worktruck. 212,000 miles. engine has a knock and i have replaced the lifters. is there any reason why i can't replace a vin z with a vortec engine from a 93 blazer. will the wiring harness xchange when i swap computers? what other problems will i run into when i try this? has anyone tried this yet? both are 6 bangers, same tranny, and i have to change fuel pumps. please help, thanks, toivo