To drive it properly yes, to get the swap done no. The auto ROM compensates for torque converter drag, the manual one obviously does not. My 84 2.5 MANUAL had an auto ecm in it when I got it and it would idle at 3k every time I came to a stop, give me an error code pertaining to VSS, and eventually lower after maybe 30 seconds. Other than difficulty in starting from a stop though it drove perfectly so you can get away with running the auto ROM and getting the manual ROM later.
An unimportant note is the ECM uses the same line for torque converter clutch on the auto and shift light on manual so with the wrong ROM you shift light will light up at strange times when it thinks it's locking the torque converter.
[This message has been edited by AsaBergman (edited 10-14-2020).]
