Brexit, the things we need to leave alone

There are many things that work fine, And should be left as they are.
All food imports and Exports, No quotas, Unless Dumping is found, Like milk below our prices.
Timber imports
Clothing, And footwear
Wine, beers etc
Cars and commercial vehicles,,,,,BUT up to £1bn trade surplus, ie with any manufacturing Country,,, Say Germany, They can only sell £1bn more to us, than we sell to them, Same with France, etc
Same for Industrial Machinery, And Heavy plant,