TunerCat questions?

[88-383]

I need help figuring out which ECM Definition File to use for my 1990 Blazer. The TunerCat website has a whole buch listed that seem like they could work. Does anyone know for sure which one I'll need. is it the $42 file?

Thanks

Kelvin

 

[southernspeed]

That's the one i use on my '91.