Okay now having had a go at BOTH my shifters. My 2nd attempt on my newer shifter worked out much better.
I went with the cable sleeve trick again, but this time I bored out the hole a bit (it has a taper anyway) so I just used a 6.5mm drill bit and reamed it out a bit(the hole is approx. 6mm)
So that worked out fine this time without any jamming so far.
Now my own innovation was to find the right thing to stick in the bottom of the hole to up the resistance. I ended up using a very short motherboard standoff. I added an O-ring to the top of it to isolate it from the spring.
It also now has a much more positive feel in Seq. Mode now as well which is a bit of a plus.
It is now VERY stiff, and well of course it has a small click in it of course. I also did the neutral mod with a rubber band, tho again I love my O-rings so I will look thru my stock and see if I have anything appropriate, as that will have much better durability and better tension.
But yeah so far so good. Im just gonna go do some TT's in GT5:P and see how it goes.