I've always used channel lock to get those flat spring clamps off but they can be a real PITA depending on what way they are rotated.
THERE you go ..... DEPENDING where they are rotated !
And on this task .. that gives THAT TERM new meaning. The shop that changed the rad before MUST HAVE HAD that tool. I think I mentioned this before- I had to pull the rad WITH the lower hose attached. I know I should have cut the hose ..., AND YEAH I wound up buying a new lower hose because it had swelled a bit .
LEADING ALL TO THIS ..... I found on eBay bid on and bought one of those cable pliers.....
$ 9.50 .... delivered to my door .... HERES the search wording.....