Preserving source IP in L4 VIP

So I created a VIP for sending log data to a couple of syslog servers. I created a L4 vip and it works fine, except the data shows up with the interface IP of the F5 which is to be expected (automap.) Since it is L4 I can't use X-forwarded for, I am wondering if I can use an Irule to preserve the source address of the traffic so it makes a little more sense when it gets in the syslog server. I am running a basic Irule to restrict traffic, would that conflict? Or since the traffic only gets pushed to the syslog servers can I do none for SNAT to preserve the original IP address? Would this have any affect on my other VIPS? Being UDP traffic I don't need to worry about asymmetric traffic do I? I am running 11.5.1, I read you can use HTTP profiles in 12 for L4 VIPs but there were a lot of restrictions, is X-forwarded for not allowed? Any guidance on this would be super helpful! Thank you as always! Joe