I've had a yellow top in my car since May 2001. The battery sits fine in the stock tray, but the wiring had to be adjusted because the terminals were reversed (positive on drivers' side, ground on passenger.
No problems here...
Bob Johann
SoundQ SVT
1998 T-Red SVT Contour #3088
2001 IASCA Pro Street 1-600 Champion
2002 SLAP Pro Street 1-600 Champion
2002 MECA SQL Master Class Champion
2003 IASCA StreetX 1-600 Champion
2005 SLAP Expert Street Champion