87 Manual Rack Steering Column Splines?
 

Does anyone know what the size/spline count is for an 87 manual rack? Pulling the factory tilt column in favor of installing a longer collapsible aftermarket column, and am trying to figure out what U joints/adapters I'm going to have to pick up to piece it all together.

At the first U joint off the column (near the booster), is this also splined, or did Mazda use something like a double D shaft?

Thanks!

Just as a follow-up, I just ended up taking the setup apart and counting. Both ends appear to be 5/8" - 36 spline.

Good stuff to post the info.
It's not a common thing to do on these cars so it's appreciated.

Too true! Unfortunately, I can't find a male splined stub shaft that will mate to it, so I will end up having to replace the U joint with one that has a 3/4" weld end on one side, and 5/8-36 on the other.

Good luck to you,and post up pics if you can of the progress.It would be nice to see.Thanks.