I smell fouled plugs from the previous misfires, just like Pdad.
There'* a couple things at play here. Intermittent misfires on a single cylinder are usually only apparent in OD, especially when under light load (a small hill). That'* usually a plug or wire, not a coil. A wire shorting out to something metal (block, dipstick tube, etc) may not happen at idle, but can during higher-than-idle rpm'*. This may have alot to do with the voltage the alternator is providing. As it raises, the spark voltage raises, allowing the arc to occur.
The 'lights out' trick may be for you, but I'd inspect all 6 plugs if I were you.
A 2-cylinder misfire is very obvious. It can be a coil, but may only be when the car is hot.
The other question I have is what condition is your alternator/battery in? This can have an effect on existing ignition problems.