ISX 15 Liquid Natural Gas Cummins 871

[Backhoe Man]

I bought (2) 2013 petes with westport Cummins 871 engines thay ran on 5% diesel and 95% natural gas.I changed the injectors,changed ecm,wiring harness, added rocker arms and fuel pump assembly. Parts came from a 2007 871 that did not have (def) but had (dpf filter). Got most of the codes cleared, except after treatment codes.Need help with this,I have insite pro but my ecm have a password on it.