I *think* all you would need is a ML cable to connect from BS4000 to Wireless TX, then ML cable from Wireless RX to BL2000. I do not believe you need an IR eye, as the ML signals from the BL2000 should "wake up" the Wireless RX.
One thing to check. I remember a while back somebody posted a Wireless compatiblity matrix. You may want to take a look at that... You may also need to upgrade the software in the Wireless -
unfortunately, there is no way to definitively tell what software is
installed without a tool - a sticker or serial number might give a clue,
but not 100%). although since you already bought the Wireless, perhaps this is a moot point. I'd pick up a couple ML cables and see what happens.
I've been meaning to test what happens with an BL Active connected to a wireless - this might give some clues as to whether what I described will work, as the active should be sending pretty much the same ML signals as a BL2000. If I get to this soon, I will post results. I do have the latest software in my wireless - I upgraded so the "timer" function would work.
Stan