Any 86-88 ECM will work. It will be a 1227170. But swap the prom from yours to the new ECM if the new one is from an automatic. An automatic prom will run but not work right in a manual. Any 86-88 ECM will work too with an 86-88 prom.
Any 84 ECM or any ECM from a 4 cylinder
will not work.You can use an 85 V6 ECM (1226869) but it needs the manual trans prom. Also, you can't swap proms between an 85 ECM and 86-88. It won't work. 85 ECMs need 85 proms.
[This message has been edited by TK (edited 10-19-2020).]