D2 Exhaust Pipe - Size

I think on my "J" series, I found 8" long, 2" dia, sched 40 pipe on a 3/8" flat plate was a good fit to match the manifold outlet, then slid a 3 foot long piece of 2-1/4" exhaust pipe over that.
Pipe is the same OD as the ID of a empty Mountain Dew Soda can as that is what caps the exhaust when its not running!
Why?
Because you can ALWAYS find an empty can!

For a 'U' series and I think "J" series the Pipe is 2 1/2 " OD . Pipe is unavailable from Cat but the Muffler 3B6217 and Clamp 2F6299 are, I bought them a few Weeks ago . Ask for "Classic Part" for the Muffler, It was about $55 aud and the Clamp was about $27 aud.
The pipe needs to 6" to 8" above Bonnet .But your Choice . We have fitted these to Both "U" and "J" series Machines and they Work real Good. LJ

Thanks for the help guys.