Suzuki 2 Strokes

As part of my T250 project, I am forced to rebuild my engine (which is a 74 GT250). Since the engine will be bored out 1mm (effectively making it a 260), the exhaust ports will be cleaned up and I have to run pod filters due to a missing air box, I am planning on installing Mikuni VM26-8074 carbs. The problem is, I need base line jetting so I don't blow up the engine while I am tuning. I am looking for suggestions.

Also, although the engine is a 74 GT250, the timing plate, etc., is from a T250. Will I be able to time the engine properly with T250 timing gear on a GT250 engine?

Will I be able to time the engine properly with T250 timing gear on a GT250 engine?

If I was you, I'd time it with a dial gauge FIRST.....and you can then check the marks on the plate
against what your dial gauge says.

Sorry but I can't help with the jetting question since I have no idea what size the stock carbs were.