The engine went into the swing arm gap fine without any work, the pivot was the same diameter.
I made up ally triangle mounts to hold the front and get the position right.
The steel tabs on the frame underneath the crankcase needed to be cut and move about 10mm. So pretty painless on the motor.
The harder part was mounting the 89 KX subframe onto the 86 frame. I cut off the existing mounts and got new ones fabricated and welded on. Then the tank had to be built that would match the front of the seat and sit well on the frame.
Looks really nice. When I heard you put something other than the '87 KX front forks on it I was greatly relieved. My brother had a '87 KX125 and I had an '88 KX125 and there was a BIG difference on the forks. The '87's were terrible and the '88 was much much better. Since you put '98 Suzuki forks on there they must be light years better.
I always toy with the idea of taking one engine from one bike and putting it on something else. Like putting a 2 cylinder 2-stroke on a light street bike. I would love to do that but have never had the room, money or time. I like that you have been able to make such a really nice bike from top to bottom.