Need some help, white sweet smoke and churning sound. Options

[IBx1]

Hello 6GC Forums! I found what I thought was a great car for my sister after her 7th gen. got wrecked, but it's having a couple of issues after sitting for 3 weeks. We bought the car with a CT rebuilt title, which means there was an insurance claim made for body repair, and NY is stupid about registering cars with non-pristine titles not from NY. I drove it for 3 hours on the highway home from where we bought it and there were no problems, but now that it sat for a couple of weeks while we're waiting for registration, there's a problem.

To start, this is a '97 fastback with the 7A-FE 1.8L engine and a 5-speed manual transmission.

I charged the battery up with my car since it got too low to start the engine, and noticed some white smoke on startup. The smoke went away, but once the car got up to temperature(needle about 10˚ counterclockwise from horizontal), the smoke came back as a constant steam. It wasn't thick, and it smelled a little sweet as if there was water in it. I'm going to check the radiator and oil caps for possible head gasket issues once the car cools back down.

The other problem is some weird churning/grinding noise coming from the engine bay, although I'm not sure what side of the engine it's coming from(sounds like it's coming from the middle of the firewall). This just started today and was constant.

Those are the problems; here are my questions. If the head gasket is going bad, how difficult is that to replace? I have some mechanical inclination from tinkering on my '02 Si, and a torque wrench good for 80 pound-feet. What tools will I need, and where can I find a service manual for this car? If I forgot to mention anything that would help, please let me know.

Thanks!

[IBx1]

Update:

The smoke had died down significantly the next time I started it up, and smelled more like normal exhaust. The churning sound is still present.