Ss springs, caltracks, monoleaf what to choose

i have a 68barracuda with qa1 front kit and leafsprings with pinionsnubber ,Qa1 rear shocks, 28x11,5 worked well with a small block in.
I going to have a 512 pumpgas engine in it now pg and 4:56 and think it will be traction issues, what woul be the recomended rear choose to get the car hooked at the track?what does the racers do? 4 link?guess it would be a mid 9 sek car, also heard leaf link is good?

When you say it worked well, what was your 60 ft time? Changes/upgrades, my vote is Cal-Tracks and Mono leafs. Can you put a taller tire under the car?