Summary of problems encountered.
Removal wasn't difficult. Replacement was difficult.
Observations.
Get help to position the UCA in the body bracket. New UCA is a tight fit and bolt hole alignment is critical. I replaced the bolt head front than MB rear.
Pass side remove air filter and unbolt the batt holder 10mm bracket for another 1/8 inch access to a tight space.
Install the inner roll bar bushing.
Insert UCA in bracket, use a punch to hold.
At this point the UCA is in its bracket and the roll bar protrudes from the UCA with one of two bushings installed.
Install (much adjusting) the UCA bolt to body.
Lift roll bar with floor jack and wood piece to allow ball joint insertion in suspension arm. If unable main UCA bolt try inserting the ball joint.
Don't tighten the ball joint. Both after UCA body bolt.
Insert front bushing half. Passenger side went on without a problem as the roll bar aligned up nicely with the UCA opening. Note: I lubed all bushings several days prior with silicone.
Drivers side a major bushing problem as the roll bar entered the UCA at about a 5 degree down angle. New bushings wouldn't insert far enough for the bolt to grab. Solution was a longer bolt. Not right but adequate. Thin washer and tighten snug, then replace washer with one of two MB washer, then both MB washers, then MB bolt and thin washer and repeat to compress the bushings. Helped with a screwdriver easing bushing into opening.
Tighten ball joints, lower the car and tighten UCA body bolts.
PITA but very noticeable improvement in ride characterisitics.