So R2 450 000 - R1 358 000 = R1 092 000 * 66.6% = R727 927.2 * 28%= R203 819.616

R2 450 000 - R203 819.616 = R2 246 180.38 net profit to business

So dividends will be

R2 246 180.38 * 15% = R336 927.057

R2 246 180.38 - R336 927.057 =R 1 909 253.32

So from a R2 450 000 sale SARS take R 540 746.61 and shareholers get R 1 909 253.32

Is this correct?
No it is very wrong. You need to separate capital from operating. Refer my post above