Hi, I've taken the ht leads off the coil pack to install new leads and plugs......but now stupidly upon removal didn't take note of which lead to which cylinder, I can't remember the order, the coil pack has 4a and 4b stamped on the 2 outlets of the coil pack, but which is front cylinder and which is rear....and is it a problem if I get them the ht leads the wrong way round? Cheers