Vent Windows and tach

[Barnyard Chevy]

I'm currently doing a frame up resto on my buddy's 72 swb and I need some advise. (1st) He is wanting to get rid of the vent widows and go with a one piece side window. I think he is crazy for getting rid of them due to the classic look, but it is his truck. (2nd)I'm going to build him a custom gauge cluster but he wants to put a 5" tach on the top of the dash. Me personally I would perfer it to be in the cluster to give a clean look. Do ya'll have any suggestions on convincing him or do you think build it the way he wants? Thanks for the help