Systemic for a large pony tail with mealy bugs?

I have a 30 year old pony tail palm with mealy bugs. It is planted in an inside garden with a skylight. Can't move it and it is difficult to reach the top fronds. Plant is about 8 feet tall. Am using insecticidal soap and wiping down fronds I can reach.

Spraying the soap and an insecticide where the fronds branch out from the stalk. I heard that mealy bugs go there in particular.

1. Is there a good systemic I can use?
2. Would it be a good idea to pull or cut off heavily infested individual fronds?

 

I had the same problem with my 20 year old plant. I could not get a systemic because they are now banned here. I ended up creating a 50% solution of rubbing alcohol and put it into a spray bottle. Sprayed from above into each rosette. Repeated every 5-7 days until no more mealy bugs.
The plant survived, the bugs did not.
I would only remove the leaves if they are brown and dead. The rubbing alcohol solution soaks nicely in between the live leaves where the bugs are hiding.
If there bugs on the leaves you can dip a q-tip in rubbing alcohol and draw the q-tip along the leaf.
Could you stand on a chair (carefully) to reach the top of the plant?

 

Thank you, I will try this. I have a ladder, but the ground is too soft.

 

Put a flat board under each pair of ladder legs, and they won't sink into soft soil.

 

I have the same problem with a smaller, potted pony tail palm - would it help to re-pot it as well as the alcohol solution?