I don't think I kept a copy of the bill of materials for that one.

However if memory serves (and it very well be failing miserably so don't hold me to it), I think the oil cap is most likely the same one as used on Ansen/Keith Black/Mopar Performance Gen 2 hemi valve covers.

Possibly this one
https://www.summitracing.com/parts/dcc-5249949

Might want to go to Ansen and see if they will share any dimensions.

Rich H.

Esse Quam Videri