Fwd clutch and flywheel are exactly the same except the spigot bearing
You can use a 4ac starter but best to use a 4age one due to the heat of the exhaust going over it
Yes you need a sandwich plate, use the one on your 4ac engine since that is the correct rwd one
There are lots of throttle cables you can use just go to a wrecker with your old one and find one slightly longer
KE70 and AE82 both work but are a little on the long side, I believe the corona cables are a better fit