guys I think i have an airlock in coolant heater only blows hot when
you rev the engine and temp gauge has risen over halfway for the
first time in 2 years
Is there a certain way to fill it up and/or bleed it?

Thanks

 

try draining down, refill coolant, leave cap off and turn heaters on hot on full and then top up fluid as necessary, or before you try this try squeazing the coolant hoses to help pump the airlock out.

 

Whats the best place to pour it in?

In the plastic thing by the bumper or the little header tank?

 

use header tank mounted against intake runners.
and as stated below squeeze hoses repeatedly to get all the air to the header tank. and keep tank filled up while doing.
plastic tank is only the expansion tank. fill it up to required level that's it.