I've had shaved handles on my 64 for bout 25yrs with no prob
I also put them on the Rambler and added cables inside just in case I have a prob cuz I also put electric windows..... so with no power I'd be up the creek with no paddle...... if the kit you buy doesn't have the cables the kit runs about 50 bucks...... I just went to the local bike shop and bought the hand brake housing then picked up some 1/8 cable from the hardware store (cuz bike cables come cut to length and they weren't long enough) some wire loom clamps and some cable clamps and made my own I did both doors for about 22 bucks compared to 100 for the kits

MM64