PAN Tokenisation in APACS30 traffic

We are looking to replace a token in apacs30 authorisation traffic with the original PAN using an LTM and irule before forwarding to clearing bank. There is very little publicly available information about the apacs30 format and no google hits for doing this using the F5.

 

Has anyone tried this before? and if so can you give us some pointers on how this can be acheived

 

Many Thanks,