Jinma 254 Fuel pump bleeder leak

Hi.

After an emergency fuel hose fix i could not get my jinma starting, so i decided to bleed the fuel pump after reading another tread here.

Opened the bleeder screw (The one where there’s no paint on the pictures) and got out some air. The engine starts and runs just fine. However i must have overtigthened the screw (I thougt i was careful). It now just rotates, and when i start the engine it pops out about half a centimeter and fuel is squirting all over the place. If i press it in with a screwdriver it holds with just a minor leak, so i fastened it with the steel thread under the two nuts in the corners (As you can tell my mechanical english is not very good)
The tractor is usable but it is sweating quite a bit fuel.

The tractor was flown out to my place on an island by chopper, so a trip to a repair shop is out of the question.

Any ideas how i can fix this ?

Is it possible to unscrew the four nuts on the top lid and lift this off (of course after removing the three hard fuel lines) without needing to reajust timing, and without having a lot of small parts flying around ? Will there be room on the inside of the lid for a nut so i can somehow just manage without bleeding and replace the bleeder valve with gaskets and a bolt/nut)?

Or can i perhaps remove the manual pump easily, and remove the inspection lid with the four machine screws and somehow reach the inside of the bleeder valve with a finger and a nut ?

Is there any pics/drawing of the inside of such a pump somewhere ?

Any ideas appreciated

-Goffen