[cabmandone]

I can't tell you the size but after using the Wiseco ring compressing sleeve, I'd recommend getting one. I used one my brother loaned me. No real worry about breaking rings by having one catch.
If what I found online is correct, you have a 97mm bore.

The model for my 3.2 was RSC09500 Yours would be RSC09700

Here's a video my brother did of the ring sleeve in action. Only note would be to load the piston from the bottom rather than the top because of the taper the cylinders have.