2 Sub on 1 Reciever with only 1 LFE connection

So I have a Pioneer Elite VSX-23TXH. It has a single Pre-Amp out for a subwoofer. Currently I have a HSU VTF2-MK3 connected to the Pre-amp. I have an older Klipsch KSW10 that I had for like 10 years and was thinking of connecting in as a second sub in the room. Probaly nearfielding it. That being said my question is how do I connect both Subs to a single preamp? Can I just get a y rca jack and plug that into the Pre-amp on the reciever. Then on one Y Connect the HSU sub with the single LFE jack and then connect the other Y side into another Y jack and put that into the L and R in the KSW10? Since it's a preamp signal I am assuming this is the way to go but just wanted to make sure.

Thanks. That is what I thought but just wanted verification before going to get cables.