I've got a line on a DIYPNP from a 1999 and want to figure out what is required to get it to work on a 1994. Or if it's even worth the effort.

I've tried searching, but Google doesn't have much to offer as far as answers go.

Anyone have an idea that may send me down the right rabbit hole?

 

Here is how you would've built it for a 94:
https://www.diyautotune.com/support/...5-mazda-miata/

Here is how it WAS built for the 99:

https://www.diyautotune.com/support/...0-mazda-miata/

Go through these pages and figure out where they are different and rewire it.

 

DIYPNP kits from 90 all the way to 00 are identical -- just need to rewire as said above.

 

I went from a 95' to a 00', just put the pin outs side by side and get busy it's not that hard.