Don't bother with the VT2000 going into an A4000. You won't get the full functions of the card. NewTek redesigned the VT4000 card to fit in the A4000 and work with AGA chipset. Would be much more benificial to install a VT4000 in the A4000, instead of hacking the A4000 case.
I had to hack the A3000Tower case to fit the VT2000 card as it was. Managed to obtain a used VT4000 to replace the VT2000 but the card doesn't want to sync video.
Just my 2 cents.