I tried swapping out weights with the advance kit specified from MSD for the streetfire and I didn't like it; the timing came in all at once at around 1800 (from 18 to 32 in about 200 rpm). All the different kinds of springs did was move the all-in point around but there wasn't a smooth curve so I went back to the stock setup. I have not played with shaving or changing the weights as that would be somewhat final so don't want to go there yet.
I checked the weights movement and there is no binding anywhere.
The MSD advance kit 8428 is the one I'm using now (since it is the one actually for this unit - the pro-billet kit was not)
I put a bright green line on the balancer since the day I got the engine and its still bang on.
I'm now actively saving up for a pro-billet unit but until that time I'm going to play with the Holley setup and maybe, when I have patience back, play with the ignition advance again
Thanks for all your continued help