Amiga 4000 64MB Memoryhack, without motherboard-cuts
A while ago I found a hack how to add 64MB or RAM into the Amiga 4000 motherboard:
To get there just check http://www.amibay.com/showthread.php?57613-64mb-fastram-to-your-A4000-mobo
ONE SIDENOTE: this hack will NOT work on Rev D Amiga 4000 (those with the 030 soldered onboard) or the A4000T