I have a 1977 vette with stock control arms i found a company that has tubular upper and lower control arms. Is their a advantage to changing them?

If the uppers are adjustable you can take the shims out and set the alignment with the adjustable upper. The shims can fall out if you don't keep a check on the tightness of the nuts on a regular basis.

And if they are adjustable, you can probably dial up more caster than would be possible with the stock setup. Take care. Tom Worthington

I have tubular control arms on my Nova. It works just fine, but if I could do it again I'd spend the money on good bushings, springs, and shocks rather than the control arms themselves.