Ive been trying to set the points gap on my RT3,but to no avail.I have the piston set at 2.9 below top dead centre as mentioned on this forum,trouble is when i come to set the gap,(which is awkward to say the least), the points spring back once tightened.I know that theres a cam on the inside of the flywheel which it bears on,but its very slight.Now ive only tightened the flywheel up by hand ,not torqued it up,as i will no doubt have to take it off again,To set the gap does the flywheel need to fully torqued up.

Just my methods & others do it different.
At 2.9 the points should be 'just' touching, or in other words 'just leaving' each other. So set them to touching then eyeball them & run the flywheel back a fraction then come forward & see if ya recon they're starting to move at that 2.9 moment. But first check the pointer tab or bend it to align with the slot in the flywheel window at 2.9 for easy future reference. Would be a good idea to torque it up first but if reasonably tight you should be ok, not finger tight. Just loosen the points screw & set then resting on the cam then tighten them. If they creep while tightening just keep at it by slight movements. Then check the open gap with the flywheel slot about as far as you can go & still get a feeler blade in. Might be best not to know incase it opens another can of worms, but go for 15 thou max & 12 minimum which you 'can' pretty much guess by eyeballing.
Just to add, if the gap is out of spec--12 to 15 then you can't do anything about it without altering the timing. New points needed if its 'too far out of gap spec'. So timing is the important bit, which is why i said might be best not to know the open gap--within reason. Also, when torquing up the nut hold the flywheel with a sold tool to get a positive feel. I overtighten mine i know but never let go--or probably won't come off when i want it to.

The correct piston position is 2.9 before top dead center. Not below. In other words make sure you are not after top dead center and trying to time it.

Thanks once again for the info guys,managed to get ithe points gap right ,but still no spark,so its back to the drawing board

Oh, ok, no spark. Points need to be clean or at least contacting which you can verify with an ohm meter on the black wire up to the loom. Slight movement on lowest ohms setting between open & closed & only a fraction of flywheel movement forward & back over 'that' point to see a result. Is the wire onto the points mounted right & insulated from earthing so it gets through to the spring wire. Black up to the loom can be connected direct to the plug coil to bypass the loom & switches. Just make sure you can stop it if the throttle runs away, which it shouldn't of course--just saying.