Your Questions:
1. Not sure, however, a 225 should be fine.
2.Plently -
Hypertech
Superchip
Diablo Sport (http://www.2dsperformance.com/diablosport.htm)
Dennis Reinhart(http://www.reinhartautomotive.com/index2.ivnu)
5. Bilsteins heavy duty, Edlebrock IAS shocks, or P71 (Ford Police) shocks
The Bilseins are the roughest and firmest. The Edlebrocks are a little softer and the P71 shocks offer the greatest firmest for price.
6. Please clarify this question.
7. You probably do not need a larger throttle body unless you are running with a supercharger or you have ported heads. A throttle body spacer is really useless for our vehicles.
Do some searching in the "4.6L forum" on www.crownvic.net