Your stock trailing arms should be able to hookup just as well as a 4 link. Your front mounting point (where the arm hooks up to the crossmember) is probably too high up. If you were to lower the mounting point (move it closer towards the ground), you move your "pickup point" further forward. It's hard for me to explain how it works, but if you were to draw an imaginary straight line from your rear axle where your arms connect up to where the line would contact your frame, you would see that the point is well behind the rear of your motor/trans. By moving the front mounting point lower, you extend that line further up your frame and provide more leverage, therefore more pressure is applied to your tires and the ground. Sorry about the rambling... Mud racing provided lots of information about rear suspension setups and how they work.. hehehe
