12V Conversion for Selecto-speed need some instruction

The diagram is very straightforward but I need some assistance with this problem(s):

I have a Borg Warner 4 post soloniod

Push button with a wire to the Park or neutral safety switch under the tranny cover.

Key switch

and trying to get the tractor to start just in Park and not in all gears now that I have completed the wiring with this conversion.

Has anyone converted their 871/81 etc Selecto-speed and how did you do you it with a 4 post solonoid, push button starter button, and key switch? I can use your help.

Tom

From the push button terminal one wire to tranny cover/park safety switch. Other push button terminal wire goes to one small post on the solonoid.

On the other small post on the solonoid a wire goes to the key switch contact so when the key is turned on it energizes the solonoid and then sends current to the push button.