Need help with 2008 5.3 and a 2015 6L80

[toroz06]

Ok so I?m doing a 5.3/6l80 swap on a 1987 Toyota Land Cruiser, have been reading a lot about this swap and I?m confused on the steps that I need to do, I have a wiring harness for the 5.3/6l80, the ECM is a E38 the tcm is T43. I have read that I need to pair the two computers, then some people say it need to be done with sps2 and other said with hptunner i should be able to do it since the are both used computers. I guess my question is what is the proper way of doing it? taking into account that I no longer have the 2008 Chevy avalanche or the 2015 Tahoe, I have access to both programs sps and hp I just need to know what I need to do on them

[blindsquirrel]

Those are incompatible. There was a major change in the comms protocol in mid-2009, so you have an ECM from before the change and a TCM from after. You need either a pre-2009 TCM (or transmission), or, a post-2009 ECM (and compatible operating system).

[toroz06]

Thanks for that information, when I find a comparable tcm, what do i need to do to pair them together?

[blindsquirrel]

Are you trying to do this without service manuals?