Hi Uniserver,

Actually I have this unit (the 3.5" version): 

http://www.ebay.com/itm/Stratos-Technology-CF-Aztec-Monster-Brand-New-From-Japan-/271927477329?hash=item3f50240451

It connects as a storage device no problem (self terminated and has jumpers for the SCSI setting).  However the user manual states this for booting:

About MacPlus


[SIZE=10pt]Mac Plus does not boot from this card normally. You must cut #40pin RST fuction from flat cable. CF card volume is recommended under 2GB. [/SIZE]

So I'm thinking only a cable mod is needed?