[Beejay]

Boxhead,

I emailed the seller. Here is his response.

Ben

Hey there, thanks for your interest in the transmission mount.
The mount will fit a T56 as the mounting holes on the T56 are listed as 3.75" or 95.3mm which matches the mount.

It is designed to be a direct replacement of a Chev type mount and fasteners are provided to suit a range of crossmember thicknesses.
Height = 55mm
Width = 55mm
Hole pitch (gearbox) = 95.3mm
Hole pitch (crossmember) = 38.1mm

Shims are also available if required which can be fastened to the base of the mount using the 2 small additional holes.

If required a custom top or lower section of the mount can be made up to suit an existing application.

Please dont hesitate to contact me directly if you have any further questions.

Regards,
Mark Georgiadis