transmission control module?

[musubk]

I swapped the engine from a 1990 automatic legacy into my 86 BRAT, with the original 4 speed D/R. In the process of thinning out the wiring harness, I came across a part which I believe is the 'transmission control module' for the automatic in the Legacy, it's a decent sized box with three wiring plugs going into it. I left it in place at the time, but now that I'm trying to clean up and pack all the wiring away in the BRAT it would be nice to get rid of this bulky thing. Do I need this? Obviously I no longer have the transmission it's supposed to be controlling, I'm just worried that it'll cause trouble with the ECU if it isn't there.