I think Govtech J are ADs and K are DDs, but i could be wrong. But overall Govtech in salary comparison, i do know that their salaries are higher when compared to MX equivalents.

Just a generic example, as there are AD/SAD at MX10, DD/SDD at MX9. Its a wide range.

EG. Govtech J AD > MX11A AD
EG. Govtech K DD > MX10 DD