For an extra $15, the M/C kit with mounting parts is a deal. It's going to take some fabrication, a threaded pushrod and the right parts/retainers to make sure the pushrod is retained in the master cylinder correctly.

Typically I would cut and thread the original, use a long nut with a couple of jams to create a turnbuckle affair and use the adjustable rod the comes in the kit. You could probably use the two halves of the original and make it adjustable.

Did I say to make sure the retainer has a fresh rubber ring on it and is secure in the master cylinder?