Question for tech people on older ampeg 410 he cab

So I have an older 410 He (92' or so) that I am refinishing. The older HE cabs like mine were rated at 200watts @ 8ohms. Mine has the Eminence 32 ohm 10's (wired parallel I am assuming). I want to install new speakers with an 8 ohm total but also want to up the rms wattage handling. How exactly can I do that? I realize wattage isn't everything but would still like to increase the power handling a little bit.. Here is what I don't understand. According to the research I have done, total watts is the same in both parallel and series (including series/parallel). So 2 200w speakers together equals 400w. My Ampeg PR-410hlf is rated at 600 watts at 4 ohms (I think). Thats what, around 4oow @ 8ohms. If the older 410HE is 200 watts rms, were the older eminence speakers only like 50watts or something? Here is a link to one article I was looking at. Understanding Basic Electricity of your Amp and Speakers | ActiveBass. Thank you for any help on this.

 

Maybe I didn't clarify my question well enough. My He cab has 4 - 32ohm speakers for a total of 8ohms. It is rated at 200watts @ 8ohms. The speakers themselves have nothing on them except the 32ohms and the item number. They are the standard eminence 10' #86-032-01. The current model of that same speaker is rated at 32 ohms-100watts. How can my cabinet be rated at 200watt rms with 4 x100watt speakers in it? Wouldn't it be a 400w rms cab?