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Cadillac Replacing Fuel Injectors

Two of the things ASG in Indianapolis mentions regarding the Caddy 4.9L OHV engine is that the fuel injectors are weak, and that they are the same ones used in the TPI Camaro's.  The Cadillac use Rochester injectors, but I have not been able to determine the exact flow rate used.
 
Now, following this along, the 305 ci TPI Camaro used a 19 lb injector.  Recalling that the 4.9L is about 300 ci, it would be a short leap to believe that Cadillac used the same 19 lb injectors.  Actually, during research, I should note that the two injectors are one digit apart
in AC part number.  So, I suspect the Caddy uses an 18.x lb injector custom to the design.
  
Anyway, although the Caddy injectors cost $60-$75 each, one can purchase new TPI Camaro 19 lb injectors for $200 for a set of 8 injectors. 
  
So, I ordered the Camaro injectors, and managed to install them over last weekend and this.  In testing, the car is either the same HP, or has gained around 5 hp at upper RPM's; see web2.airmail.net/nunnally/sts/homedyno2.htm for road dyno charts.
 
Changing the injectors is a bit involved.  I also changed out the accessory belt, since it has to come off during the process.  To reach injectors 1 and 3 you have to unbolt the power steering pump.  Injectors 6 and 8 are under a water hose, and the connections between the fuel rail and the supply, so they were also a pain.
  
I have read that you can also get "take off" 19 lb injectors from www.slponline.com for $100 per set of 8.  Since the camaro guys change these out right away when they put on a supercharger or other perf adder, you can get "slightly used" injectors there apparently.
    
In summary, changing to new 19 lb injectors did not add much power.  It did show that these injectors are interchangeable for the caddy ones, and a cheap replacement.  During last week I ran the car with 4 old injectors and 4 new with no problems.
   
I should note that I had previously had my old injectors cleaned by one of the oil change-it places (Kwik Kar), so while they have 123K miles on them, the cleaning may have been effective, and may be sufficient rather than replacement.