I happen to like having two floppy drives in an A2000 for the odd game or two that won't work with WHDLoad and have two disks or for your save game disk ....mighty handy to not have to swap disks constantly.
I'd personally take a look at someone's GVP combo card with the original mounting bracket and make my own. It's just a piece of simply formed metal. The way the A2000 m/b is laid out, the back of the combo card is the ideal spot for a harddrive without losing a zorro or isa slot for the future. As for the 25-pin external scsi header, I believe all the combo boards have a 25-pin header right on the board, so just run a cable from there out to an external port.
