Form 7203 Line 3g - Net Capital Gains

Shareholder of a disposed S-corp, so I need to file a 7203 this year. I'm having a bit of an issue with line 3g - "Net Capital Gains". In TurboTax forms mode, it says to add lines 7, 8a, 8b, and 8c and enter it in line 3g.

Is this correct? I'm not sure it is - aren't lines 8b and 8c from the K-1 1120-S subsets of your net long-term capital gains that are taxed at a different (flat) rate? 28% for collectibles and 25% for section 1250 gain? I have unrecaptured section 1250 gain and on my schedule D it seems pretty obvious this is a subset of my overall net LTCG, not an addition. Which would make the instructions for line 3g wrong - should be just the addition of lines 7 and 8a, correct? Or am I off-base here?

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