Ok so i have a small concern, I bought the stang i have now from this 50's something guy who said it had a 302 in it. Ok the car started out as a 4 banger and had an engine swap. i went yesterday to get now plugs and wires for it and got plugs for a 87 5.0 302, got back home and their to big go back so i took one back with me, the plugs i ended up getting were for a 289, ok theres half the problem a 289's firing order is 15426378, set the plugs and wires back up to that it didnt work, so i went and got on my alldata and got the firing order for a 302/351 which is 1-3-7-2-6-5-4-8. but got to looking even closer the the intake manifold has ford 289 stamped in to it. what the heck do i have ?