I have a Delta Leland kitchen faucet and I want to replace the springs & seals. I have the handle off but I cannot remove the dome shaped cap from the base. It gives you some very small flat spots for a wrench but when I try to twist it, the cap and base twist as one part in the counter. How can I hold the base piece in place without damaging it and get enough of a grip on the cap to twist it off? Are there some special tools I could get?