I am installing a 136" m-10 suspension into my 121 xcsp I have just about every thing figured out except the measurement between the drive and the front swing arm mount as this is where it all starts . If you know or know anyone who knows this measurement it would sure help me to get this project on it's way to becoming reality. Thanks in advance.

I assume that you have the tunnel plates for the M 10. I used zx ski doo tunnel plates and a polaris hole template. Every thing was out of whack that way. I just fit the tunnel plates in so that they were parallel to the top of the tunnel, and the front torque arm about .250 from the 9T driver and it seems to work real well.

thanks for the input . I just sat down inbetween my old 121 suspension and my new used 136 and started brain storming and I thought what is the difference between the two then it came to me 7.5 inches. So I set the rear of the 136 7.5" behind the 121 and measured the difference between the two front swing arms and moved the foward mount hole and bingo the thing went in and all I had to do was fabricate and install the rear mount.

I got the transfer complete. Didn't get seat back from apolstry shop yet it's black also.