Yes, internal spring compressor is the only thing needed.
When I first did this job I tried the control arm thing. It was a nightmare and I ended up using ratchet straps to get things held in place and aligned to get the job done. It can be done but it's just a hack and really not worth the cost of a spring compressor.
Internal Spring compressor is the right way to do it and I've done it several times with the tool without issue . See my post about using a spacer with the Sealey tool.
https://www.volvoforums.org.uk/showt...ghlight=sealey
Good Luck.