just gone to 1×9 setup and at the moment running 32 t front 11-32 rear , I have seen some cassette with a 11-34 so the 34 t would give me an even easier gear ??? or would the 2 extra teeth not make much difference ??

It would give you an easier gear yes.

It would make a difference, but you may not notice.

I see cheers I also see CRC selling a 12 -36 not sure if this is possible ???

As long as its 9 speed it should be fine. Its probably a 29er specific one, but as far as I know will still work, but you may have to adjust your mech.

im thinking of going 1×9 but do I need a chain retention device above the chainring?

I have a 32T ring that works fine for where I ride, but also a blackspire stinger on the BB mount.

I dont really want to get a new chain guide jobby as the stinger works great – I think I’ve seen ones that mounts on the seatube where my mech was but its on a five so the space there is limited. Where can you get these type? Who sells them?

To go with your Stinger you’d need something along the lines of the DMR Chain Cage. The Paul’s Chain Keeper type guides would not, by my reckoning, be much use at somewhere like the place which shall not be named – you’d probably be losing the chain off the top of the ring quite regularly.

Yes, the extra 2t does make a difference. It means my 22t is pretty much redundant anywhere on Cannock Chase. But thats just me, old slow me.