Anyone have recommendations on where they start on brake bias adjustment? Also how do you check the brake bias prior to going on track?

I generally use a small ruler (same that I use for toe) to measure the difference between the two clevises and the inside pivot point inside the brake pedal (assuming you don't have the washers on each end that I see on some cars.) I'd suggest starting conservatively with more bias toward the front (the measure should be less than the rear) somewhere on the order of 8/32-10/32nd difference between front and rear measures, then leave it up to the driver to dial-in the balance (I assume they can tell the difference between front and rear wheel lockup under braking.)

I have run into situations where cars have the front and rear master cylinders reversed or the initial thread settings on the clevises are too far off to make appropriate adjustments so you want to make sure that there's enough threads available on both clevises to move in the range of 6 to 12/32nd of adjustment (front biased.) Also be careful that the clevises don't bind on the brake pedal and that the master cylinder rods are equal length and not binding the adjuster rod on the edge of the brake pedal as this can change the pivot point inadvertently.

If you want to get really high tech, put brake pressure sensors and a math channel to tell the F/R%. That said, it is still a matter of feel and you just have to see where lockup occurs first on track and adjust from there to minimize one end locking up first, with further adjustments due to your preferences and conditions. I have not done the former, but in another similar car, weight-balance wise, I am about 55% front bias.