need help c10 rear suspension

[low69chevy]

Like title says ordering more parts for my c10 ls turbo build and trying to get all the parts ordered so I can work on it in December when I go home for the holidays here's where im at right now I not sure if to
1) keep the trailing arms with adjustable qa1 coilovers and a pb crossmember and a good anti roll bar
2) get a ladder bar setup with the adjustable qa1 coilovers
3) get a adjustable 4 link w/the qa1 coilovers
truck will be street driven and raced on weekends so trying to make a decision on the rear end I'm going to keep the 12 bolt and already recieved my moser Gridle cover etc for it. Also what rate of springs should i start with on the rear i know they'll have to be adjustments etc just want a base line to start off I believe they're 12 " springs thanks In advance