91 3.1 spark plug connection

Is #1,3,5 on the back of the motor by the firewall or in the front?Car runs if I hook the plugs up as 1,3,5 in the back but the intake says #2,4,6 is in the back.If i hook it up acorrding to the intake it won't run.
Timing chain jump or is intake wrong?

Forget it.1,3,5 is by the firewall.I found it in my 1990 lumina factory service manual.Sure is stupid 2,4,6 is stamped by cylinders 1,3,5.Go figure.

what you are seeing is the intake RUNNERs are stamped, the runners cross the motor to get to the proper cylinder.

on a 3.1 the rears are numbered (left to right) - 1,3,5 and the fronts are 2,4,6.

since the firing order is 1-2-3-4-5-6 you can pair up the coil packs 1,4; 2,5; and 3,6. Each coil is triggered sequentially so all you have to do is get wires 1,4 (for example) to the right pack, they can end up on either terminal.