License question....67 or 72?

[C20-67_N_MO]

Okay here's the deal.....

I now have two trucks, one is a '67 3/4 with a good cab and front clip.
And the other is a '72 1/2 ton that the cab and front clip is in rough condition but good bed.

Now my plans are to use the good cab and front clip off the '67 and place it on the 1972 frame and drive-train.

So my question is once I get it all together and ready to license what year would I use to goto the DMV?