6n2 1995 problems

well my stereo was hard wired ina t some piont and the stereo seems to switch on when it wants. it wont switch on with the ignition either athugh there is a fine bodge where they have wired in the connectors. the ariel connector is held together with insulation tae also. can i get a new ariel connctor and solder the wires back together? also te earth wire has been removed where is it best to route this and bolt it to?

also my speedo and rev counter dont work the speedo needle makes an awful noise and wobbles on zero and the rex counter doesnt work. all the rest on the cluster do does anyone know what i may be able to do or am i going to have to resort to a ew clock set?