I try not to ask for help like this but this one is screwing my noodle.

I have a costing spread sheet that I have managed to manipulate to give me a monthly cost role up (if exists) VS part number. Part numbers column c, months row 3.

On another sheet I'm trying to list the part numbers next to the cost role up and relevant date (each part number may have multiple entries)

I just need to do a "SMALL" for the "date" row (Row 3) on my costing sheet "IF" the "correct part number row" (or a fresh MATCH/VLOOKUP for the part number) has data in it. Or some how have the small return the Column INDEX number. I could then use INDEX to return the correct date and value using SMALL and Column B (the number of costs per part number, so if there are 3 instances that column currently list 1,2,3 before starting the next part number)

So close..... but this last bit is a struggle. Its a shame SMALL cant return INDEX Column numbers.

Does anyone know how to get a "SMALL" to lookup a row (based on a column search criteria) and check if the column has data, if so include the that column header in the "SMALL"

Update...

Thanks for your comments. I've stripped out the problem into a separate sheet to make it a little clearer. (I'll upload if possible).

I've also completed the rest of the excel to show the whole process. In doing so I've discovered Headers are automatically converted to text and so added a column to work around this using "DATEVALUE".

The goal is to list the number of costs related to a part number so.... if 500111 has had a cost role up in 3 different months it will list them in the cost report. So.... part number, relevant column "date" from "Cost data" sheet and relevant cost (@that part number @ that date). if I can get a list of dates from "Cost Data" columns and put them in Column D "Costing date (text)" next to the relevant part number i should be sorted. I've highlighted the column in red on the new screen shots.