By the picture this is the information I think what the accelerator pump fits and the number 17061073 AC Delco for 1984 Chevrolet G10-30 Van   Rochester 2 BBL  the item has been discontinued.  The number on the box is mess up. From end to end measures 2-3/4 inches long, spring 1-1/8 long compress on end cap has stamped 257 HH,BB on it.  Please look at the picture to see if it is a fit for your vehicle, it is guess work for me without the actual part number.  Thanks for looking.