8 Inch Rims
Models using 8" Rims prior to the 2018 Model year take the Standard 8" Rim.
Starting with the 2018 Frontier 8x8 Vin# 41791 and 2018 Frontier 6x6 Vin# 18906 in March 2018 Argo switched to an offset 8" rim on all Frontier 8x8, 6x6, and submodels going forward. If your Vin# is prior to the numbers above your unit takes the standard rim.
A simple way to check what rim you have is to look and see if you have air fill valve stem on both sides of the rim if you do you have an offset rim.