The Nova II unit only has two wires--it has instructions,basically you just snip off the wire that went to the points from the ignition coil ,hook one of the wires to that wire,the other wire goes to ground...some coils require the wires to be reverse polarity ,the instructions say if you get no spark at first,swap the wires around and test again..
Those modules will not work on every type of coil,or flywheels with "multiple magnets" for a charging coil--some older Briggs coils had 3 "legs" on the armature and they claim it wont work on those also..the original coil also needs to be in good condition for it to work,and the engine needs to be spun over a bit faster to create a spark when starting,than it would with the original points and condensor..
I bought three of those modules,had poor luck with them--two created no spark no matter which way it was wired,I thought the coil was bad,but it works great when I put the points and condensor back in..:dunno:..
I'm thinking I got two someone fried by putting 12V to them and returned them un-used perhaps.."junk out of the box"...
One has worked OK on an old 5 HP vertical Briggs though...
Sometimes you can simply bolt on a later model Briggs coil that already has the electronic sensor in it and it'll work with the original flywheel magnets..on a 3 HP a coil from a later push mower might work...in some cases the magnets on some flywheels are the wrong polarity though,and it wont work...you used to be able to have the flywheel re-polarized,but I heard Briggs no longer offers that service..perhaps the flywheel used with the later engine that had the electronic coil may also fit your engine...only one way to find out..