Correct wiring for JBL 4350 and Smith horn

Hi all, For a JBL 4350 speaker what would be the most correct way to add a Smith horn and 2405 positioned on the top of the speaker? Currently I have the internal 2440 driver in series with the external 2440  driver for the 2397.horn.  Also the same set up for the 2405 internal driver in series with the external 2405 driver mounted on the top of 2397 horn. 

Second option choice up would be a 3120 crossover (1200 hz ) for the 2440 and then wired to 3106 crossing at 8000 hz for the 2405. for the  tweeter. No internal connections  for either drivers. I thought these external crossovers would match the internal 3107 pretty close.  These would be connected to the  same terminals that are driving the internal 2440 and 2405 and also the 2202 drivers. Using a tube mono block amp  with approx. 70 watts. I was feeling the 1st option had less electronics in the signal path. Parts for this set up might be somewhat hard to get and maybe pricey. 
 Not sure if I am giving all the info needed to give good suggestions