Yeah, that 'strong repugnance' lasted until April 24, 1863 when the confederate congress added their own income tax. Here, see for yourself.
Because of the high volume of bilateral trade with Europe several Souther states proposed moving toward a radically lower tariff regime themselves.
States cannot set tariffs on imports or exports without consent of congress (Article I, Section 10) so where was that a threat?
In secessionist scenario, Northern ports would find themselves in direct competition with low-tariff Southern ports.
How? Prior to the war a Northern importer paid the tariff at New York or Boston. Had the south seceded, then an import destined for the same Northern importer would have paid a tariff at the southern port, and then another tariff at the Northern port. All you are doing is adding tariff and transportation costs.
What is intuitively obvious to most casual reader of Southern writings of politicians and other leaders prior to the Civil War was the unfairness that these leaders perceived concerning the existing Federal tax regime.
That's not what Alexander Stephens was saying before the rebellion in December 1860:
"In 1832, when I was in college, South Carolina was ready to nullify or secede from the Union on this account. And what have we seen? The tariff no longer distracts the public councils. Reason has triumphed. The present tariff was voted for by Massachusetts and South Carolina...Yes, and Massachusetts, with unanimity, voted with the South to lessen them, and they were made just as low as Southern men asked them to be, and those are the rates they are now at."
Curious assertion. From that link...
"...and the income and profits derived from any source whatever, except salaries, during the calendar year preceding the said first day of January next, and the said income and profits shall be ascertained, assessed and taxed in the manner hereinafter prescribed..."
In other words, an "income" tax that exempts salaries. So what were all those non-salary things that were being taxed? A brief examination of that bill indicates that they were almost all types of excise and sales taxes, not income taxes. Most of them were taxes on "luxury items" such as tobacco and alcohol and various entertainment and travel related industries. For example, this includes a 2.5% tax on sales by auction, a fee based tax of 5% on alcohol wholesaling, a flat annual fee for pawn broker sales, a property value assessment-based fee for hotels, a percentage fee for tobacco sales, a percentage fee on theater ticket sales and other similar entertainment activities, and various percentage based taxes on different types of liquor sales. In other words, hardly anything even remotely resembling the "income tax" you purported to have been contained in that bill. It was a nice try though - attempting to pass off sales and excise taxes as an "income tax." But as is typically the case with everything you post, it simply does not withstand scrutiny.