I believe you can buy a spacer for the 6.1 crank snout that will put the timing chain in the correct position. Molnar Technologies sells this.

You must use the vvt chain because of the front cover, just lock out the vvt.

The only way a 6.1 cam would work is with the use of an adapter by A.C Nutter. They offer a snout that goes over the existing cam but it is very expensive. You would be better off getting a vvt cam.