The heat is well controlled by enclosing the RPi in a ‘Flirc’ metal case which has plenty of heat dispersing effect especially outdoors. I then mount it with its plastic bottom outwards to optimise the WiFi performance. There are people who fit an RTC, but this will require a higher clearance case, and a different approach to heat sinks. I used to attempt to use a GPS dongle to set the location and the clock time. I had problems with poor GPS reception and interference into the very low level satellite signals from the RPi’s own ‘digital noise’. These days I simply turn on the RPi, use VNC Viewer from my laptop, and set the date and time to match the laptop clock using the terminal command <sudo date -s ‘2021-10-21 21:10:50’>. I don’t need to change the geographical location very often but when I do go travelling I set the location from the data on my iPhone app ‘ScopeTools’.