Click box for multiple deletes on custom prices for custom investments

When I import a .csv of multiple transactions for custom investments made in a foreign curency it adds two highly different values for each transaction to the custom prices section. If I'm DCAing something this can create a lot of extraneous information and mess with the capital gain calculation. It would be nice to be able to selct all of these and delete them (or for them not to pop up at all) instead of having to delete multiple instances (impossobie)