I show Sr # 7371 - 8957 as 1940 production.

thanks, hey spraguem, I live about an hour south of you near Ellsworth...small world

No you don,t just use later parts in older engines but you must go by the old part number in the NPR & it tells you what if any new part replaces the old number.If there is no change of number then the same older part is whats used.Sometimes a replacement part calls for another part or two to go with the new part so it makes them compatable to the older engine or whatever current engine you would be working on. What happens on here little if anybody on here has NPRs or fische to run down all these changes (part numbers)so gets confusing for most average people.When I was working a portion of your time was used in ordering parts & other info. needed to complete a job correctly.