Where is the temp gauge sender located? If it’s under a head bolt or spark plug (as most air-cooled temp gauges) It will read those 230-240 temps. these are not liquid cooled engines and are clearanced as such when machined.
I’d be more concerned with oil temperature in an air-cooled engine if I were you. Plugged oil coolers are the biggest VW run-hot culprits.
If you have all the OEM style tin and hoses connected properly, the oil cooler is good and it’s got enough oil, you’re good. Don’t worry about sealing the engine compartment…every see a VW powered dune buggy or sand rail? No sealed compartments there.