Small Engines (Lawn Mowers, etc.): replacing briggs engine on snapper mower, engine model type, snapper mower

Question
QUESTION: I'm replacing the engine on a cannibalized snapper mower. I've taken off an old 8hp B&G engine with electric start, (prob. late 1970's model) and have a new 17.5 hp B&G engine. the starter wire (large black) is obvious, as is the "stator'? - red/with matching connection on engine (which feeds a box on side of engine with a yellow wire/green connector/black wire going into engine)- the question is:
I also have, coming on the mower (in the harness with the back starter wire and red wire) a yellow wire.  also, near the throttle linkage was a black wire (small) that was connected (on the old engine) to the throttle linkage area. ON the NEW engine I also have a connecter that has a grey and black wire and appear to connect to the bowl on the carb.
engine doesn't start or turn, beyond a quick click. I don't know the solenoid's condition, but wires & connections are good.
What do I do with the yellow wire (and the small black wire) and what about this new connection on the engine (grey/black wires - carb. bowl) ?
any answers or thoughts are greatly appreciated

ANSWER: Have you checked out this site:

http://www4.briggsandstratton.com/miscpdfs/RNT/alternator_replacement.pdf

http://www4.briggsandstratton.com/miscpdfs/RNT/ignition_wiring.pdf

Six pin swith picture:

http://i210.photobucket.com/albums/bb268/MOWNIE/KeySwitch1.jpg

The small black wire should be the engine shut-off wire.  If you remove the new engine shroud to access the ignition coil the wire should run to the ignition coil.  You can connect this wire to mower's shut-off switch.  

The grey/black wire on the carb is a fuel shut-off (anti-afterfire) solenoid.  The black is ground and grey is connected to 12 volts DC when the key is in the on position.

What is the Snapper mower model number located on the Snapper sticker.  It should be a 5 digit number.  I need to look up the mower to see which key switch you have.

Also, send me the engine model, type and code number so I can look up the engine information.

Eric

---------- FOLLOW-UP ----------

QUESTION: thanks a million for the help
I had seen the pages above. Assume you're thinking that the easiest way is to start over and ignore the current wiring.

the body (assuming the key came with it) is for a snapper SR930 (the deck and steering are not)
the new engine is 31C707  type 0026G1 and code is 100311ZD  (it's a 17.5 briggs, brand new)

need to know where to run the wires.
thanks!

Answer
Is your Snapper model number 301014BE, Rear Engine Rider Series 14?

If so, I looked up the switch and the switch is a 3 pin switch.  Remove the key switch and look on the back of the switch for some small letters.  There may be an "I", "B", "S", "G" or something similar.

There are a couple of options but both will require running additional wires.  You can either use the existing switch, if one of the poles has 12 volts DC when the key is in the run position, to connect to the carburetor solenoid.  This would be the easier method.

The other option is to replace the 3 pole switch with a 5 or 6 pole switch.  The new switch would require a new connector and you would still need to run a wire for the carburetor solenoid.

Can you connect the battery to the mower and verify if one of the poles on the current switch has 12 volts DC when in the run position?

Eric