300SDL overheats

[CANDIDE]

Overheating.
My 87 300sdl overheats. AC works great, 35F at vent.
Car runs great, plenty of power and good mileage.
History:
Original thermostat came out in pieces.
*replaced cracked cylinder head (#14) with #20, super clean from machine shop.
*replaced coolant tank.
*replaced coolant tank cap (20lbs pressure type).
*replaced water pump (beck arnley)
*replaced thermostat (MBZ 80 degree C from dealer)
*replaced radiator ( Behr)
*replaced top and bottom radiator hoses.

I define overheating as:
Ambient temp is 85-90 F.
* during 4 mile climb (highway 50, Bass lake grade) temp with ac on is 105 C.
* during a 3 mile grade at 25-30mph with ac on temp is 110 C.
* On flat freeway, ac on, temp is 85-90 C. Going downhill it drops to 83C.

I have removed the upper radiator hose, while parked on a hill, and filled the hose...
several times.
The coolant tank is full, slightly above full mark when at operating temp.
I have 2 electric fans and a custom shroud instead of stock fan.
Plenty of hot air being emitted from fans.
I have not flushed cooling system...yet.
Heater works ok after about 20-30 minutes drive.
Today, I drove my usual route home and temps exceeded 110C. When I got home I let car idle,
until temp gauge showed 95C. I used infrared non contact thermometer to measure head ( at injector 2)
to be 235F.
Radiator hose from cylinder head measures 227F and lower hose measures 222F. With old radiator,
I measured a 45F difference from top hose to bottom hose.
The overheating problem has gotten worse with the new thermostat and radiator.
It appears that the coolant is not going through the radiator enough to generate a
significant temperature drop.
With ac off, temp drops by 5-10C.
I'm stumped. Since the ac is cold, I would believe that the fans are doing their job.
But, obviously I'm missing something.