Crosmember swapping question?

[62jimmy]

I am looking to swap the crossmember out in my 62 GMC to replace the torsion bar setup and get disc brakes, 5 lug etc. I bought one set up which the frame and crossmember turned out to be bent on, so I am back in the market. I have a line on a 65 crosmember/suspension setup. Since I'm going to use drop spindles, the fact that its six lug and not disc brake doesn't really matter as far as I know. Is there any advantage/disadvantage to using this setup for the conversion rather than the later 73 to 87 setup? Just want to make sure I'm not overlooking something obvious.

Thanks,
Jeremy