OK, so I called a local place and they had Denso o2 sensors. They pronounced it "DenZo". I think I will try it. It has to be better than mine.

So should I get AC delco, just to be safe? And, just to clarify... is a crescent wrench ALL that I will need? I don't have many tools at all, just some screwdrivers and plain old wrenches, so I want to make sure I have everything I'll need.

I used a 7/8 wrench with a little positioning crescents make me nervous unless you can use them with a open palm, but the 7/8 worked and gave me the leverage I needed. Be carefull with the connector and spray some silicone or put some di-electric grease on the contacts so to assure a good connection and keep the moisture out..

I attempted to undo my connector, but the way they attached it to the support is weird.
I am not 100% sure what to unclip

There are members on this site running denso with no problems whatsoever, including me in all of our cars.

Frequently (from the factory) there is a little blue safety tab. Remove that and then the connector will come apart. Remove the push clip from the bracket holding it and the fuel lines. Then the O2 will be able to come out once removed from the manifold.

Wow, that'* exactly what it is. Thanks man..

The front O2 on a 1998 SSEi and the 1999 SE (as listed by rockauto) should be an AFS109 (25312203). If you get the 5% discount, it should balance out, but here it is at another good AC Delco online seller:

http://www.rmsautoparts.com/proddetail.php?prod=AFS109

I've used them about 5 times with never a problem. I use the Paypal option, but I think you can use a credit card direct. They have great customer service at 888-658-4675 X101. They cater to the B,F, and Y-body crowds, but stock or can get anything AC Delco.

If you go www.rockauto.com (I've happily used them too), a current discount code is 650010587533 through 06/26/07.