how can i get one esc two work on two receivers?

[mavrick0]

I'm assuming you are wanting the ESC to power both RX's? If this is the case you can use a y-harness but you'll have to unplug the signal wire from the RX that is just being powered by the ESC. Otherwise both RX's will be trying to control the ESC.

Now if I'm wrong and you want both RX's to control the one ESC then you'll have to figure a way to tell it which RX is controlling the ESC. Not a hard thing to do with a micro servo and a micro switch hooked to it.