Thanks for those insights. I saw the angled cut on the recommended video. These don't even look like that! These look like someone tried and returned this product -- probably for this reason.
BTW -- For all y'all who recommended spending the extra $$$ to get the complete unit -- I'm still enjoying the learning process. I'm most frustrated with not having the correct tools at hand. And hubby would like some hot water to take a shower. I'll send him to the bathhouse if he says another word about it! LOL And, yeah, this is a time-consuming job. You definitely wouldn't want to hire someone to do the initial work of unhooking it, whether you just replace the tank or the whole thing. Time-consuming, therefore costly. So now that I've seen all the innards, I'm over this project and just want it DONE!!! I suppose it would be done by now if these misshapen parts weren't hindering my progress.
Sorry for whining...