Importing table with existing Record ID#s

If you want to actually preserve the old record id and not change the Key field of your new table you can simply do a blank import up to the highest record id in your old table, import your data and then delete the records ids you don't need. So lets say your highest record id in the old table is 4356 - in your new table just import 4356 records so that all the record IDs exist. Then actually upload your old data since the record id's will now exist. Final step is just delete any records that might have already been deleted in the old table and you're set. This preserves the old record id without having to make a new key field.