Other minor details:
The A4000T differs from the A4000D in several ways:
1) the Zorro slots are not on a daughter board.
2) there shouldn't be any battery damage because the AT A4000T came with a coin battery, not the horrible leaky barrel one.
3) There are three small daughter boards known as modules. The ports module is connected to the mobo by means of two ribbon cables. The other two modules (the AV and disks module) are daughter boards of the mobo and can be replaced if damaged. You just have to find them (I got two modules from Vesalia recently).
4) There is no 2mb SIMM for the chip ram, it is on the mobo in SMD form.
5) There's no external floppy drive port
Couple of things to check before you get the Miggy:
1) The claw clamps on the bezel section. These can be damaged if the previous owner has been ham-handed while taking the thing off to get at the drive chassis.
2) Make sure the floppy works (this might seem obvious, but it is very important)
And...did I say get the A4000T already?
:-)