need help with my suspension 1970 gmc

[bigboybodry]

I need some help with my suspension guys. My truck is a 1970 gmc bbc truck th400 12 bolt rear end. I have no idea what it weighs and the chassis guys around here do not want anything to do with it. I took it to the track last friday night for the first time with the new engine/setup and it isn't even trying to transfer weight to the rear tires. I have the qa1 stocker star shocks on the front with the upper shock mount moved to the top of the frame. moroso front spings but I don't remember the part number. the rear has strange single adjustable shocks and moroso springs and again I don't know the part number. the battery and 20 gallon cpp fuel tank are mounted behind the rear axle. I called moroso and they want to know the front and rear weights etc....... also I have heard about lowering the trailing arms on the crossmember whats to this? There is a video of the run at the track in my sig. I did a burn out and then they put some vht down and still spun broke loose when I bumped second also. Thanks for any input