collecting parts to eventually change from a hot air to a 87 setup,,on the exhaust,do I need both sides of the headers? I know I`ll need the pass side,but ,how bout the driv side. Are they the same (84/85 and 86/87) ,if so, then I could use my 84 driv side header ,and a 86/87 pass side header. Also ,how bout the cross over pipe,will the hot air pipe work on above set-up ,or would I have to use a 86/87 crossover ??---------Jack