chevy carb to tbi engine swap help?

Ok so i have a 1968 Chevy c10 that i recently had a carb fire on which burned up all the electrical under the hood, i havent had the money to fix it yet but my buddy just told me he would sell me his 89 1500 with a 350 that. Has tbi and i dont really care for the truck cause its trashed inside and out but the engine runs great so he said he will sell me the truck for 500 and im just wondering if the engine will drop right in and if i can just transfer the ecu and all the stuff from his truck to mine, i know all the sensors will have to go in with it but also his truck was a manual and mine is automatic can i just throw my tranny on or do i have to do anything there my buddy said i will have to get an ecu for the same year truck and same engine just out of an automatic he says the ecu thats in it now is made for a manual but i just dont see why that would make a differance is he right do i need to get a new ecu for an automatic and will my tranny bolt right up cause my truck has a turbohydromatic 350 or 400 i cant remember but i think.its one of those two i just know its a 3speed automatic anyways if anybody could let me know if this will all work that would be great

'89 M/T will work fine as far as ECU/ wiring harness. You need the entire harness but it's been done and it's not overly complex being that you are not changing the '89 engine around at all.... Even if the truck was a 700-R4 truck, it would still work because the 700-R4 is not computer controlled