I am currently painting my 71 right now and have had some great success so far ..wet sanding is time consuming and puts water on possibly unfinished body panels(exposed steel) which later might expose a rust problem later
I am finishing up my Truck this fall and have found that a good final paint finish does not require a wet sanded finish. I use urethane primer my final sanding on the primer is done with 320 sand paper, then a final overall scuffing or smoothing is done with my Scotch-Brite pad.
I so far have finished about half my truck and and it looks amazing..I do plan on wet sanding and buffing...but not prior to final paint and clear coat