if they BOTH use denso then you are on a winner. if its ANYTHING like what I have seen in the 33/34s here they unit can be: clarion,xenavi,alpine,matsushita all for OEM.
only way to truly work it out is to strip it. mind you that unit still will not be cheap. figure $3-4k at a minimum.
this is what I mean by a swap out:
to:
there is a LOT to change to get to that stage. the AC controls have to be redone for one.
how bad do you want it?