I probably should have checked the bug tracker for this problem.
http://bt.x-cart.com/view.php?id=43598
Suggestions from the bug comment to use Custom CSS (System Settings->Look & Feel->Custom CSS) proved quite useful. The original problem was that the text didn't wrap. Changing white-space to "normal" allowed the text to wrap, but didn't honor the line feeds between the lines of text. Using "pre-line" solved the linefeed problem, so at the bottom of the Custom CSS panel, enter the 2 lines listed, then tick the "Use custom CSS" option and then click the Save button.
.checkout-block ul.payments li label {
white-space: pre-line;
}
The Description text field now shows each line separately and honors the linefeeds.
Cross browser support shows that "pre-line" is not supported by IE. YMMV
Kevin