May not be the issue, but for good measure, check the routeing of the belt. FYI, after having the system open replacing all those good parts, as mentioned, it may take a few bleeds and some running and sitting to get the bleed process completed thoroughly.

Also, do not "use the coolant", put a big pan/tray under the bleed screw area and catch it to use for the next bleed fill. This is one place rovers can be green

In regard to temps, with that new t-stat and a new radiator, you should see idle temps in the low-mid 190's I would think when you get this all sorted out. I have my original radiator at 152K now with new head gaskets and new 180 Motorad t-stat and my temps range from are 194-195F when normal mixed hwy/city driving to 198-200F after some long idling in traffic, IIRC. I run about 197F on the hwy when towing.

 

If the radiator has been replaced, you should not get overheating.
and you did put in a 180 Degree REAL Land Rover 'stat right? Not a Motorad?

At 210 Degrees F you should and MUST have the AUX fan on and blowing.
if not there is your problem.

At idle, the temp should creep to 210 and then stop there as the AUX fan will come on and LOWER the temps to 207 or 206 and then the aux fan goes off and the temps rise again.

With the landrover 180 degree, I never go over 203 or so now ever.

 

"Then seal it up. Run it, turn it off let it cool a bit and bleed it again...this is a PITA."

This part you got wrong... don't bleed it again until it is STONE COLD and the level in the overflow tank has settled to its lowest point.

And while you are there you might try flushing the heater core before you reconnect it, The flush will give you a heads up if there are any issues with the core, like if all the contents drain into the cabin... Or it's clogged with DEX... then fill it as much as you can with some more green coolant before you put it back in the system. priming as much of it as possible... reconnecting hoses will add some more air of course.

Thats a good idea to catch and re-use the coolant from the bleed screw.

 

I've found that following the rave procedure for bleeding the system actually works. You just need to bring the engine to operating temp, let cool fully, top off, and repeat a few times.

 

1)Have you confirmed that you don't have a head gasket leak? http://www.summitracing.com/parts/li...FY1r7AodsicAjg

2)Make sure that when they did the heater bypass that they didn't kink the bypass hose. The hose needs to make a tight U-Turn and if they just took a standard straight hose and bent it, then it may have a restriction in it.

Getting a D2 for $1,500 is nice but I would suspect it has some type of major issue. What does the bottom of the engine and bell housing look like? Is there any coolant in the oil?