You can remove the other ends or cut the hoses and rejoin the with couplings and hose clamps. Not sure what year you've got, but when I flushed my 2000, I had a little improvement but the problems just came back in less than a year.
On those early generation trucks, the hearer core replacement isn't too bad a job. There's a video showing it done in less that an hour. Took me about three.