Lots of things to answer here. Here's a few points without making it too long. I used straight 30 wt oil, same as I've been using
Done. I just took the old carb off...put new one on...put on water muffs and fired her up. Runs fine. My auto by starter wasn't working. For the $30 bucks
If "horrible grinding noise" was coming from the chain driving the cam, and the timing slipped, could account for not turning over with plugs
Any jet would be considered an orifice plug, but they are all different in their design and usage... high speed, slow speed, intermediate speed, etc.
The timing is set-up using the great Joe Reeves' WOT method, but that sounds like a good idea getting a 19-3 blade as well as a 17-4 blade. The oem prop