Hello, friends.
First of all, excuse me for my English. I am from Russia and I write through a translator.
Today I got a connecting rod Hot Rods 8608 from Honda CR250R 02-07. The big end of this connecting rod coincides with ours precisely, which allows it to be installed without alterations. The length of our connecting rod is 132.5 mm, and the piston has a compression height of 33 mm., In the sum of 165.5 mm. The length of the connecting rod CR250R is 125.3 mm, and if put the Wossner piston from the CR250R '83 with a compression height of 41.2, we will get a total of 166.5. It will be necessary to put several gaskets under the cylinder to raise it by 1 mm. Piston sizes are 66 / 66.5. What do you think about it?

Hi
From what I have read on the forum most people go for a trx piston
This thread maybe of interest to you
viewtopic.php?f=1&t=10260

I like the sound of this but it can also apparently be done with the TRX piston, CR250 pin and bearing then Hot Rods 8111 rod (KTM 250/300 90-99). Your method will also work and spacing gaskets under the barrel is pretty common to set squish on 2 strokes anyway. in fact I believe the KTM kits come with various different base gaskets of different thicknesses. You may even find that 1mm extra height is manageable but you would need to measure the piston height at TDC to make sure its not going to clip the head and you have at least 1mm of squish.