I made my own boxes from 3/16" because the ones you buy are a little flimsy and the inside diameter is too big, i also put extra holes in. As said before weld tubes through the chassis rails and fit the rear hangers, i also beefed the rails up on both sides of the tube. Mr P I think he only races in the winter. Mick
69 Dart GTS 440 mopar .590 cam, Edelbrock heads, 3200# best et 6.45, 106.78, 10.14, 132.88 mph, 1.47 60ft best 60ft 1.36