I bought the dual electric fan kit from Mid-America, thermostat turns it on at 190 and off at 170.  Problem was, it ran all the time in hot weather.  Something more going on.

 

When I removed the old fan shroud to install the dual electric kit (and discard the belt-driven fan and clutch and pulley), I could peer down between the radiator and the AC Condensor.  Lots of pine needles, old leaves, trash.  Less than ideal air flow.  No easy way to reach it and clean it.  Decided to pull the radiator and have it cleaned and resealed (considered new, but too expensive).  While it was out, swapped the old water pump for Mid-America black-painted hi-flow pump.  Replaced the thermostat with a 160-degree hi performance.  New hoses, and I removed the old vac-operated heater shut-off valve (couldn't believe that it was still working after 25 years anyway) and replaced it with a ball valve in the same spot.  (This means I have to open it manually for cold weather.)

 

Once all back together, here are the results:

 

The fan cycles on and off like a Japanese import, even idling in 90 degree weather!  On about two minutes, off for three of four.

 

In 70 degree weather, the fan only comes on at traffic lights.

 

Below 70 degrees, the fan doesn't even come on.

 

In all these cases, the dash temp gauge never goes above 190!

 

The engine runs more peppy, never pings, and feels as if it is saying, "Ahhhhh!"  This is with the original cross-fire injection intact.

 

I have also removed my air pump and all associated plumbing and fixtures.  One of the one-way valves blew backwards, and all my plastic plumbing and the three-way valve melted into a heap.   When one of the air injection tubes blew open while driving, I went home, cut the rest of them off, and inserted short, self-tapping metal scews into the holes, sealing them with hi-temp exhaust epoxy.  Sealed the cat air tube by cutting it, crimping it, and sealing with the hi-temp epoxy.  Disconnected the vacuum to the EGR; in fact, the only vac lines I left intact are to the brake booster, the headlights, the dash heater controls, and the MAP sensor.  Simpler, cleaner, cooler, easier to work on, and it feels better than a 25 year-old 350 with cross-fire.

 

These things, I found out, are made by Dewitts, they are the greatest thing since sliced bread. They come with PLENTY of wire, relays, sensor, and everything you need to install it properly. This is a great piece of hardware!