Hi dvvrue95,
I've recently added a CF card reader to my A4000 in the same way :-)
The IDE > CF adaptor on my Tandem card shows up as 'oktagon.device'. With my Oktagon SCSI card fitted as well, FindDevice of IDEfix97 found the CF card as Unit 100 (without my Oktagon SCSI card fitted it was seen as Unit 0).
Here is the mounlist of my CF0 driver from Workbench:Devs/DOSDrivers which can read 64MB, 1GB & 2GB fat formatted CF cards:-
/* compactflash.device $VER: 1.21 (19.10.2002) */
/* fat95 file system by Torsten Jager */
FileSystem = l:fat95
Device = oktagon.device
Unit = 100
Flags = 0
LowCyl = 0
HighCyl = 0
Surfaces = 1
BlocksPerTrack = 1
BlockSize = 512
Buffers = 20
BufMemType = 1
BootPri = 0
Stacksize = 4096
Priority = 5
GlobVec = -1
DosType = 0x46415401

I also had to download 'TandemCD.dms' from
HEREand put the file 'AT' into Workbench:Expansion for it to work. The 'AT' file is set to Manufacturer 2092 and Product 6, which is how the Tandem card is seen in the 'Expansion Board Diagnostic...' screen of the 'Amiga Early Startup Control'.

:pint: