4 & 5 pin ECUs

Pardon me if this is a dumb question, but the pictures imply that the resistor can be mounted upside down, and hence you can connect the resistor backwards - is that correct?

If you have the factory connectors with the plastic locating “nubs” intact, they fit into slots in the ceramic resistor so it cannot be hooked up backwards.

It you don’t have the factory connectors or the nubs are broke off, it can be connected backwards. Probably wouldn’t run well ( or maybe at all) with 5 ohms in place of 0.5 ohms.