Rick, you will likely get a few different opinions about this. What I've learned is that you can use the stock crossmember (you'll need a thin rubber pad...about 1/8 or 3/16" thick. Measure the gap, get the pad, make holes in it, raise the rear of the transmission gently with a jack, slide the pad in, line up the holes and use a couple of bolts/nuts to attach it. But...you may not like it. If your transmission has any bearing noise at all (and many of them do), that noise will be telegraphed into your cab through that crossmember. When I did this the noise was almost as irritating as chewing on foil if you have tooth fillings...a little bit goes a very long way. It sounded like I had a bad throwout bearing or the pilot bushing was going bad or maybe the flywheel gear was spinning the starter gear. So I did away with it and haven't had any problems. Let's see what others think.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end