Your argument is logical but the Third's tough exterior doesn't affect how strong his brain is, getting electrocuted by his hell stab via Kazekage's iron sand would just overwhelm himI personally thing that the Third Raikage > Third Kazekage on the basis of two things;
His stamina/hype;
The Third Raikage was shown to have a ridiculous amount of Stamina, as he battled10,000 Shinobi for 3 days (I think it was) and he came out on top.
Obviously people will assume that these guys were just fodder, but either way, even if they were, 10,000 is a lot, and for him to even have the Stamina and strength to keep fighting for that long is ridiculous.
His black lightning and his assumed speed that comes with it;
Obviously this guy was a beast, for him to go toe to toe with the Gyuuki is hype enough, but this guy even had the Black Lightning, a fearsome Kekkei Genkai indeed. Now, we know that using a Raiton Shroud increases your speed and raw power as demonstrated by the Raikage, so if Black Lightning is an improved version it is logical to assume that he'd be even faster with this particular type of Raiton.
Overall he wins because of his speed, power and his stamina. tbh we haven't seen much from the 3rd Kazekage so it's harder to determine who would win, but personally, I'd go with the 3rd Raikage
Also Black Lightning would just electrically charge his iron armour meaning it would be even more dangerous to touch/hit
The iron armour's ideal shape is a incomplete sphere that doesn't touch the ground or the Kazekage but the inside allows the Kazekage to stand on the ground.