2002 mercury grand marquis

Replaced rear brake disc, calipers, pads, and brake hoses. copper sealing washers supplied with the brake hoses do not easily slide over the banjo bolt shoulder like the o.e. sealing washers do. The replacements are thinner too. Upon assembly the replacement sealing washers leak regardless of banjo bolt torque. Should the washers easily slide over the banjo bolt shoulder and be more likely to properly seal?  Why do you think this brake hose to caliper connection is leaking?