Petter A1 Petrol Paraffin magneto type impulse or not?

Hi Fellows,
I a collected a Petter A1 petrol paraffin from a friend of mine last weekend he had removed the mag for someone to check it over.
I see its not a impulse type mag? I thought the A1's would all have had a impulse type mags?
Some years ago the engine was running but became difficult to start hence the reason that he decided to have the mag looked at.
Although a vaporiser is fitted there is no wee starting petrol tank on the end of the main tank.
I guess the petrol paraffin engine might have had a slightly lower compression than the straight petrol version, possibly not though being a side valve. If the petrol paraffin engine did have a lower compression than the straight petrol engine was the volume of the combustion chamber in the cyl head larger?
I currently have the head off as the exhaust valve was stuck solid and badly pitted,,,, now sorted.

The VO or paraffin A1 has a different cylinder head than the petrol engine, also has a half round tank for starting bolted to the end of the main tank and a 3 way tap so you can change from petrol to paraffin once it's running. It should have an impulse on the mag, if it is the one that bolts directly onto the timing cover then the impulse is behind the gear and may not be obvious.

Hi I'm a bit more enlightened now after having a closed look at things.
The mags an impulse one right enough, I didn't realise that the impulse doesn't work unless the mag is in the upright position
On having a closer look I see there is a tooth broken off of the mag drive gear also it appears that the pushrod that operates or pushes onto the throttle bow linkage appears to be missing there is only a very short push rod that links to the governor bob weights (see photo) is this correct or should that rod be much longer
I have a spare mag that has the bobweights and associated linkage missing, easy enough to swap over but unsure about the length of the pushrod that's operated by the bob weights. Possibly there is another pushrod that fits into the bush in the engine casing

OK I sussed out how the governor rod is set up, I should have noted that I got the engine with the mag off and in a box.
That's a pretty horrible way to have to install the mag on the engine i.e. removing the pushrod bushing from the timing case and placing it into the governor housing and then fitting the mag. I'm sure those who have done it will know what I'm on about