[bondobob]

I boxed my '57 from front to back and replaced the stock crossmembers with 2" X4" braced tubing, notched over the axle and added some 2" X 2" diagonal bracing. Believe me, it's stiff!! Unless I have my four jack stands exactly the right height it will tetter totter on opposite corners. I used 3/16" for everything. My old '66 was so flexible I vowed to never have that again. You can still see the temporary bracing I added front and rear to keep things straight. It's square and level within 1/16". Do it!