John,
First, after what I went through I hope I can help anyone stay safe in that situation. Also, I'm not saying FE-36 is worse than Halon. I just have no experience with it. The reason I say 2 seperate set-ups is that if you only have an engine fire, you don't want it going off in the cock-pit. Halon displaces all the oxygen not to mention it can slightly burn you from the cold if it hits bare skin right out of the nozzle. My crew guy accidentally discharged my system in line-up one night (oops). It took my breathe away quick. Here is how I would set-up the system.
1- 2.5 to 5# bottle for the drivers compartment. 2 nozzle for each seat. 1 pointing at feet and one at chest. Use an auto temp. trigger as primary. If they have a button to add then great.
1- 5# bottle for engine and fuel tank. 2 nozzles in engine compartment on near the firewall pointing toward the engine. This creates a barrier between you and a fire. put 1 nozzle pointing at the fuel tank between the drivers compartment and the tank. Again this is to create a barrier. Use a push/pull to trigger.
JMO. I give you alot of credit, most people wouldn't even think of this. I was amazed when I was racing. Guys would spend thousands on trick parts to go fast. Then they would buy a $79 fire suit and a $79 helmet and say they can't afford anything else. I had $2000 worth of gear I wore before you look at the fire system, fuel cell etc. I am able to write this because of it.
Your building one of the coolest cars I have ever seen and still have the right priorities.
PS. I have the fire on tape. If I can find it I'll try to load it and post it.
Later.