Yes, you can delete the T5008 slip(s) that have been imported from AutoFill.
If you have more T5008 slips than you are able to enter in TurboTax, you can add up all your T5008 slips and enter as one entry on the T5008 slip page. Double-check to make sure that the totals are accurate. Basically, add the amounts from box 20 on all of your T5008 and enter it in one T5008 slip in TurboTax. Do the same for box 21 and so on.
CRA is fine with it being filed this way, keep your documents available if they request to see them.