When I first wanted to install Redhat 8.0, I used autopartition to partition the drive for me. Redhat installed great and works good but I recently re-installed it but this time I left about 6600mb of free space. When I tried turning this free space to vfat, I got an error that the maximum size I could make it was 2025mb or so. I want ALL the 6600mb tobe a vfat partition to set up a dual-boot system. Could someone please tell me how to make all 6600mb a vfat partition either from redhat setup or from inside the redhat OS itself?

Try to do it from fdisk. You can run it using
fdisk /dev/hda
(if the free space is on 1st disk)
then use 'p' to list your current partitions, then 'n' to create a new one. You will be asked if you'd like to create primary or logical partition. If you'd like to install Windows, use 'p' (primary), enter a number between 1 and 4 that's free on the list you got at the beginning. Then you need to choose the right type (FAT32, I guess). Don't forget to write the changes when it's done ('w' option).