Hold on there... You don't want to move the Instant Center forward or down as BigPun76 is suggesting. Doing that is exactly the opposite of what you want.
Read this.
The front pivot point for ladder bars (which is really what trailing arms are) is the instant center. Moving this point upwards or towards the rearend will give you more anti-squat and will plant your tires better when you launch. Since you are spinning your rear tires, this is exactly what you want. However, it's not real easy to do using the stock suspension.
You might want to try contacting
this guy:
You can barely see the stock trailing arms in this pic, and he's obviously hooking up pretty well. The site doesn't say too much about his setup, except that it is "stock" trailing arms (I would guess they are at least reinforced with something like
this ) and coil overs.