1300 engine overhaul

car now booked in for welding and paint end of next month so decided to give the engine an overhaul. When I got the car a year ago it was a non runner, been sat for 15 years, brakes and clutch seized. I gave the engine an oil and filter change and had it briefly running, it had fuelling issues and due to leaking coolant pipes I didn’t risk running for long. When it did start it sounded good with no smoke so my question is how far do I go overhauling the engine?
I was planning to get an overhaul kit from Eurosport, so basically all seals, head gasket and timing belt, should I be going further? Unfortunately I’ve got to keep a tight rein on the budget as the bodywork and respray has used most of my budget. On the other hand with the engine out I would rather do things now rather than having problems after it is back in the car. Any advice greatly appreciated.

No smoke, no rattling, no steaming, starts okay, no serious leaks, oil pressure okay - the makings of a good engine that you should think twice about pulling apart. Changing fluids and belts is a no brainer, but going further you should have a good reason to spend the money and time. You can get the cylinder compressions checked which will tell you a lot about the condition of the bores and valves.
However, if you like tinkering the engine is very simple and so pulling it apart is not that difficult if it is on a bench, not so when in the car. But costs will likely rise e.g. a new head gasket will probably mean reshimming the valves, and those who have done that job will know you are always short of the right sized shims