This kit will also work for a C5, C6.
If you plan on using a C4, be sure that you have the larger 164 tooth flexplate style bellhousing (Ford also made a 157 tooth version). An easy way to check that is by measuring across the inside of the bellhousing to see if the 14.25” O.D. of the 164 tooth flexplate will clear; the 157 tooth flexplate is about a full inch smaller.
PLEASE SPECIFY IN ORDER NOTES: what bellhousing you have & if it is C4 or C6 AOD.