Coolant is going into the engine and pipes and heater core, but not the radiator :/ but it was when I had the no name thermostat in it, ironically...
So what happens if the jiggle valve isn't positioned in the top centre? Just curious of the consequence, don't worry I installed it in correct

You dont need to raise the car.  Have the two bleed points open with hoses up and fill slowly until the coolant level in he radiator bleed hose, the heater box bleed hose and the coolant filler neck are level.  Recheck after running the car and add coolant if required.  This is the only way (that I know of) of ensuring and checking the system is full.  Make sure heater is set to hot.
 
Never had any dramas following this process.
 
Cheers

raising the rear end is only to fasten the process, it doesnt do anythign else. you dont HAVE to do it just another way,  i have found that when raising the rear end and squeezing the radiator hose just under the radiator cap (the S bend one) the coolant seems to drop in level faster, then i lower it back down and pour in more
its much faster than waiting for the coolant to slowly drop in level then keep adding small amounts.

Not putting the jiggle valve at the top would hinder the air getting out when you refill, and may even mean some air is trapped in the thermo housing.
 
Although the book says the system is supposed to hold 14 liters, with my car (3SGE) I can only ever drain out about 9 liters.
I assume the overflow bottle may hold a couple of liters, and that would be included in the 14 liters capacity.
Also in my motor, I have no block drain tap, so some coolant would stay in the block.
 
BTW, raising the rear  with car ramps is great if you want to change a thermostat, because you then only have to drain out about 2-3 liters from the radiator tap and catch it in a plastic dish.
That lowers the level so nothing runs out of the thermo housing when you crack it.
 
The drained coolant can then be  poured  it back in later with the car still raised and you shouldn't have to re-bleed the system.

Hey mate the car's been at the mechanic since Thursday. So far he said the thermostat is opening very late - only after 15-25 mins of the engine being turned on so something else might be causing that eg lack of coolant to pressurise. Compression test is good so I think my HG might be okay.
I was supposed to get a call on Saturday morning assuming everything went well but it's Monday morning now which means they may have encountered the same symptoms as me and trying to work it out. In a way this is nice to here (more correctly: presume, lol) as I'm quite confident in my drain/refill/bleed procedures (without sounding arrogant here)

I've been a bit slack from updates but anyways I got the car back about three weeks ago from mech. Seemed okay for about a week or 2. It's not slowly overheating anymore but the temperature gauge is erratic now and it just flips up to max - seems to stay there for quite a while. Usually it comes down when I step on the throttle to let the water pump circulate. Mech says if it overheats when I drive hard then it could be head gasket  It just gets worse LOL. I've never been able to track this car since I bought it
Today was the second time gauge spiked again. Felt the radiator and it was cold.
I'm gonna try get a coolant pressure test to check HG's integrity. If that's good then next I'm gonna change ALL the hoses to OEM Beams + modify the radiator to have a proper bleeding hose. Gonna be a bit of a struggle seeing as I just quit my job and exams coming up fast but I need to be ready for Wakefield so I can't hold back
Been having thoughts of swapping the car for a Clubman but I've decided to keep it til Nationals next year...

Huh? A/C? You mean heater? It's been set to hot for months now making me all nice and sweaty...
Last method I used was winding the filler cap to one click and letting it warm up (not hot), then open bleed valves and checking the level after.
Laugh anyway