I wish I had found this thread earlier. I just went through a restoration of an Extreme.http://www.retrobike.co.uk/forum/viewtopic.php?t=228182
This one is 21" c-t-c. I am not tall, but have enhanced legs. Makes bike fit difficult. I may get a no setback seatpost.
BTW, does anyone know what the two brazeons are for on the "bottom" tube by the BB? Not enough clearance for a bottle.
I assumed it was for a bottle cage, but I haven't tried to fit one. I said earlier that it could be a crudcatcher mount, however looking at mine I see that the braze ons are offset and not central on the tube.
I don't plan to use them anyway though, I'm just gonna put some ano bolts in them
I always thought they were for a bottle cage on my Extreme. As you said they are offset to the left side of the frame making it easier to get a bottle out, not that you would ever use them.
I would go with the blue repaint on your bike it reminds me of the 91 Haro Extreme, it should look good when finished. I think the Haros are a bit underated being Taiwanese but they ride pretty well and IMHO look pretty good.
Good luck with the build.