Sales kits with alternative parts as child components

Hello all,
We are trying to set up sales kits where you can pick alternative parts depending on the customer request. The idea is we’d only have to create 20 sales kits with many alternative part options instead of hundreds of specific sales kits. I have set up alternative parts for several of the components of the kit.
When i add the sales kit to the order line, I do not see a way to choose an alternative part. If I put an individual component on a sales order line, the alternative parts option works fine.

Is each component of a sales kit supposed to create a separate order line automatically when added? I see there are “sales kit lines”, but there is just one line for the order with the sales kit. My thought was if each child component of the sales kit were on a separate sales order line, then the “alternative part button” would be enabled for each of those component child parts of the kit.