The timing can be adjusted, but it's through the computer. No need to do this really.

You do not want just the cap and rotor, you want the full thing. If you have time to wait for shipping, I can give you a # for a Chevy dealer that gives us cost + 10% on everything. I think it is $230, with the new vacuum harness that is super highly recommended (more or less required, I won't replace an opti without doing it). Then you get an AC Delco opti. With these motors, you really don't want to use any other sensors than AC Delco. But, I'm a stickler like everyone else. So, I stick to the AC Delco Opti and AC Delco O2 sensors, and mass air meters. Other than that, I personally don't care.

I don't know that the radiator needs to come out on a Camaro or not. I'm used to the Impala LT1, which has a good 2 feet between the motor and the fans. The pully does need to come off. You remove the 3 screws around the outside, not the big one in the middle. If you hit it with PB Blaster, WD40, whatever, you *should* be able to wiggle it loose. If not you will need a puller. I've done a couple with a rubber mallet when I didn't have a puller around. Water pump does need to come off too.

There is a bleeder on the upper radiator house input thingy. The system is reverse flow cooling and absolutely needs to be bled. The thing is the anti-freeze kills the optis. So, when you are bleeding it, do everything you can to not get the anti-freeze on your new opti.

I would also replace the waterpump while you are at it. You can pick em up for like $40-60, reman units, locally. If the old water pump is bad, it may be dripping anti-freeze out the weep hole on the bottom, right onto your $200 opti.

And, while this is all apart, you might as well just go ahead and do the spark plugs and wires. It's a pain in the ass with the water pump in. I would do the spark plugs through the wheel well if you can, with a like 3 foot extension.

I would not replace an opti ever ever ever ever ever without it being an AC Delco. I would rent a car, or beg for rides, take the bus, whatever, until the AC Delco got there before I would throw my money in the garbage with anything else.

And your symptoms definitely sound like an opti to me.

Gonna PM you the info for the guy to get parts from.