turntable setup triangle

does antyone know the mesurments,from center of tonearm to spindle to cart,im running a thorens 145 mk 2 and need to know for rega 300 arm
This site has loads of valuable information on turntable and tonearm setup. Check out the Tonearm Database for your arm as well as the library which has owners manuals and printable protractors for alignment.
try www.vinylengine.com

they have specs of many turntables and arms.