Hi Jamie,
If it is like the ones I have, looking from the front of the engine, there is a little square "cap" on the right hand side of the tank near the needle that is the fuel filler.
I would do as suggested, flood the engine with some solvent, including the "spring", and free it up that way. An air tool oil "chaser" is recommended.
Some type of "puller" will be needed to remove the "starter assembly", IIRC, but the rest of the engine disassembles similar to the various Cox engines.
They do not possess the power of the Cox .049s, but will fly a 1/2A just fine. Aaron's first balsa 1/2A was a Sterling Beginner Zero/Testors .049 "Combo" we bought at AHC during a trip to NYC! LOL!! And it flew good, still does!
Big Bear