The transmission is a KM 132 (narrow block bell housing). OK so it 'could' have a bad bearing and/or thrust plate in it. You can buy full syncho, bearing and seal kits for them on ebay. IDK the procedure to tear down and reassemble a 5 speed but there isn't any dark magic lurking in there. I think bearings may require being pressed on and off shafts. Lots of manuals/PDF's available to walk you through the process worse case scenario. All it might need is an oil change and top up with a heavier grade - it's just one of those things you won't get an answer to until you crack it open and have a look. Holley 350 CFM is too big for for the 2.0. Weber flows 300 CFM. If the carb came off a boat then there's a good chance it's only been jetted to run flat out - not ideal for a car/truck engine.