Offset motor mounts

Hi everybody, Hey while at a car show last week, I saw a 1964 Dodge 440 with a hemi in it. What struck me as very peculiar was that it had offset motor mounts to get clearance for that great big hemi engine in the engine bay. My question now is: why can't we get some kind of offset mounts for our early A-bodies to get better clearance for headers on the driver's side?