Early 911's have a tubular crossmember, so the SC mount will not work.
I am using rubber lined loop clamps and (2) metal angle brackets. The lower is supported by the crossmember and the upper by the steering rack.
It's a little offset to one side but the hoses still seem to fit nicely. The photo above gives you an idea of how it mounts, but I will post another as soon as I put one more together and paint it.
For info, please email me.
Len.Cummings at verizon.net