If you need to do fixes on your own TM racing EN 300 then it will always be a good idea to own a Workshop Manual to keep just for a reference in case you need to know ways to remove a specific part for example the Clutch and fit it again in the right way.
TM racing EN 300 Workshop Manuals offers clear detailed diagnostic facts for the car so if something is broken it can help you determine what the situation is and how to correct it. You will be able to evaluate if you can do this yourself or that the job is too big you could make a reservation for your EN 300 into a decent friendly mechanic.
TM racing EN 300 manual