I have Ernst rails, my 1" wrench sits at 2" high. They also make low profile rails which are 3/4" high, with a wrench should be around 1".
https://www.ernstmfg.com/store/p/78-6050-30-Tool-No-Slip-Low-Profile-Wrench-Rails-Red.aspx
I built mine 30x40 with 3 8x10 doors on the 40' side and a man door on the short side. 32 or even 34 wide would be better but I make it work, during restoration one car takes up 2 bays anyways.