Hi DT
What sort of mitres are you cutting? I mean, mitred corners of a box or for picture-framing?
My friend Brian-next-door recently bought a SIP machine for making picture frames. Both he and his wife paint. The problem is that it is the length of the rebate which is important, not the overall length. It needs to match the mount, but as the rebate is underneath, you can't see the mark. So I made an adjustable sliding fence, which can be set according to the width of the picture frame stock being cut. You then set the stop to the size of rebate you want and it does it for you. Well, you have to operate the saw yourself, but you know what I mean.
If this is the kind of mitring you are doing, PM me and I'll send you some blurb and pics. I hope it will appear in a Mag Near You in the fullness of time.
Cheers
Steve