1: OEM suggested spark plugs are Denso W16EX-U,W16EX-U
2: Yes that is the resistor block, you need that for the coil.
3: try adjusting the idle screw counter-clockwise at 1/8th turn at a time, as it may be running too lean on idle. Make sure all vacuum hoses are properly installed and no leaks.
Remove all the other condensers and leave one installed, preferably the new one, replace the resistor block in the coil, it is wired in series from ignition wire to resistor then to the + terminal of the coil.