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I just did this exact modification over the last weekend (Moonlite focuser on a Meade SN8). The difficult part is not removing the corrector, that's easy. All you need to do is ensure that the plate assembly is replaced with the same orientation as before. This is easy since the 4 screws holding it on have very little play and you can ensure a near exact positional replacement by placing some kind of coloured tape across the junction and slitting it with a sharp knife so that you can exactly align the tape edges.
The more difficult part is installing the SN8-specific adapter and the the focuser itself. Moonlite sells the unit (which seems to be very high quality btw...) as an exact drop-in replacement, but it seems that not all units are exact fits (at least mine wasn't...). I had to slightly modify/enlarge the bolt holes to get the adapter to fit onto the scope. I used a drill bit to shave away some metal at the appropriate position. After the adapter could be attached, the next issue was that the original focuser hole on the scope was not quite wide enough for the focuser drawtube to rack down completely. I had to grind down the metal to enlarge the hole for that. Here I used a 1" diameter file drill bit to remove the metal around the circumference. To do all of this you will absolutely need to remove the corrector assembly. I also made sure to place a barrier (crumpled newspaper worked fine...) in front of the main mirror to prevent metal shavings from getting too far into the tube.
I imagine that there's enough variability in the manufacture of these mass-produced scopes that no aftermarket modification like this will be a perfect fit every time. All told, the installation was not hard to do and although I have not had a chance to see how it's working yet, it's a serious improvement over the old focuser.
Hope that helps.
Garry
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