Unequal length wishbones question

[Ant]

Regarding unequal length wishbones "Is there a ratio of length like 2/3rds for the top compared to the lower wishbone?

I appreciate roll centers etc. bump steer, Ackerman and the rest of it, which I dont know much about .........yet!
I have just shortened my wishbones 3/4" to accommodate Trigo wheels and the adapters for guard clearance, but have run into a problem(s) I want to use 26.5 diameter rubber, so I have set the chassis up with 4" front ground clearance and 5" for the rear, and what I have ended up with is the bottom arms angled up about 2.5" at the upright, and the top arm much greater angle - moves about 1.75" and binds in the balljoint on bounce.

Looking at making longer arms and relocating altering innner pickup points to solve this problem, and I see some good books advertised, Tune to win by Carroll Smith, and Chassis Engineering by Alan Staniworth etc may not have spelt that right. Also there is available computer programs that help with roll centers etc, but my computer is a Macintosh.

Anyone got any tips on any of the above, any recommendations or direction gratefully appreciated.