ECM change for data stream

[Lil Blu]

I am running '87 5.0 H.O. (speed density) with 5.0 heads and a 351 cam in my 289 and have failed emissions this year (clean last year, no problems, no equipment changes).  I hear that you can change from a manual trans ECM to an automatic trans unit to get data stream for diag.  I need to know if anyone has a p/n or code for which one this might be, or a source of whare I can go to find this info.

[bohntr28]

Tim Bowsher is problably the guy you want.  I am running a 89 manual computer with mass air on my 289.  I don't think it would be too hard to switch over and it would problably pass.  what did you fail on?