Piping LPG into Domestic Property

[lpghopefull]

We are totally off-grid (at my request) and the photos should hopefully outline everything.
I've spoken to 5 gas engineers and 3 LPG engineers and not one of them could understand what I am wanting to do.
Can somebody please tell me if there is such a thing as an adapter that will screw onto this meter union fitting that remains intact on the gas inlet pipe into the house?
I am wanting to connect the gas outlet from the OPSO to this.
My hob has been updated with LPG nozzles and my Boiler is LPG ready. All that remains is getting the gas into the house.
I don't want to remove the existing fitting if possible as there is not much to play on the pipe (which runs into my kitchen cupboard to a tee that is butted up against the plaster in a hard to get place).
Thanks in advance for any help.

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[Gilbertd]

That looks very much like an Acme screw fitting as used for filing LPG vehicles in Germany and Belgium and is used, I believe, on fork trucks. Normally the fitting is the other way round though, with the male end on the inlet not the female end. I'm sure it can be done though.

[LPGC]

It's easy to understand what you want to do, the problems are identifying what adapter you need and sourcing one.

Mick at LPGautosupplies.co.uk may be able to help, phone number is on the website.

May be worth trying the acme fitting as Gilbert said, though I'm not sure if your threads look finer. Mick does sell male and female acme fittings, though the other end of the male fitting is designed to screw directly into an LPG tank not to connect to a pipe.

Failing that, could maybe use the blank plug and braze or drill/tap to connect an LPG fitting to it. Or desolder the fitting to solder on a longer length of pipe with LPG fitting terminator.