The engine is a 12ht turbo diesel 85 modle hj61 land cruiser. engine will start, the base idle is low and runs rough RPM aprox 600. wind up base idle with idle screw to 1000 runs good but u can take turn the key all the way off and take them out of the ignition and the engine keeps running and you have to choke the engine to stop it

12ht wont prime,driveing & ran out of fuel,wouldnt prime up so fitted another lift pump still wont prime,presureise fuel tank fuel comes out but still wont prime?

Check to see stop solenoid is working, you may be able to do this by getting someone to turn the key on and off slowly while you are hold your fingers against the side of it.
It is the small metal (Nut) with a wire going into it for an easy description.
The reason you have to choke the engine to stop it is you have either no power going to the switch or the switch is not working properly. i would think more that the switch may not be working properly as it is meant to close fully when power is turned off, if this was working it doesn't matter how much the motor is reving it will still shut of the fuel to the pump.
Sometime these solenoids get a bit of dirt etc stuck in them s well, this is usually just a easy fix,clamp the rubber fuel line before the pump, undo the switch, clean it and refit it, then undo the clamp and prime the pump using the hand primer.
Then start the vehicle, don't try to start the vehicle before you have reprimed the pump as you can damage the engine if you don't have fuel going into it.
Hope this helps, and good luck with it.
Dont rush working on a diesel, just take your time mate.