Coil Over vs Torsion Bar
and.... you forgot that if you are going to go to this level with the factory suspension upgrades, you would probably want to address the k-member. This means removing the engine and dismantling the complete front suspension. I can pretty much guarantee that if you remove it and sandblast it like I did, you are going to find poor factory welds and areas around the LCA pivot points and the steering box mount that need attention. To see what's involved in upgrading the k-member, go to Firm-Feel's site and check it out. Its the blueprint I followed. All this to get only marginal improvements, very little weight loss ( I had power steering and 10" drum brakes) and still be saddled with the access and clearance issues with headers, and vehicle height. ( I'm using a 4-Speed).
I guess you can justify anything cost wise and for me, it came down to modern easily serviceable components that dropped my front end weight considerably, allowed me more access around the engine compartment and allowed me to lower the car to the height I wanted.