BBC for my long box 67, what problems am I facing?

[67 fleet side]

Hey guys

I've recently been considering putting a big block in my long box 67 GMC. The truck was originally equipped with a 283. What kind of problems am I going to face? Will I require a completely new cross member up front? With adding that much torque is there better pilot bearings because the stock set up seems a little weak to me.