hey just wondering how to fix this?

okay so i got some cheap *** ebay slip on coilovers.. going to put them on stock shocks..
1 of the rear shocks has this..


The middle is stripped... :-\
i need help ..
is there a way to take that off so i can put the slip on coilover in..
or do i need to buy a whole new suspension thing

 

impact gun. no compressor or allen wrench needed.

 

i think impact would be the best. if you take out the whole strut/spring and take it to a discount tire im sure they would let you use there impact.