I attempted to update a SL 7 system using the Add/Remove Software GUI 
update feature.  The update fails with:

Test Transaction Errors:   file /sbin/extlinux from install of 
syslinux-5.10-1.el7.rfx.x86_64 conflicts with file from package 
syslinux-extlinux-4.05-8.el7.x86_64
   file /boot/extlinux/cat.c32 from install of 
syslinux-5.10-1.el7.rfx.x86_64 conflicts with file from package 
syslinux-extlinux-4.05-8.el7.x86_64
   file /boot/extlinux/chain.c32 from install of 
syslinux-5.10-1.el7.rfx.x86_64 conflicts with file from package 
syslinux-extlinux-4.05-8.el7.x86_64
   file /boot/extlinux/cmd.c32 from install of 
syslinux-5.10-1.el7.rfx.x86_64 conflicts with file from package 
syslinux-extlinux-4.05-8.el7.x86_64
   file /boot/extlinux/config.c32 from install of 
syslinux-5.10-1.el7.rfx.x86_64 conflicts with file from package 
syslinux-extlinux-4.05-8.el7.x86_64
   file /boot/extlinux/cpuid.c32 from install of 
syslinux-5.10-1.el7.rfx.x86_64 conflicts with file from package 
syslinux-extlinux-4.05-8.el7.x86_64
   file /boot/extlinux/cpuidtest.c32 from install of 
syslinux-5.10-1.el7.rfx.x86_64 conflicts with file from package syslinux...

However, as there is no "find" command on the above GUI (unless it is a 
control or escape sequence of which I am unaware), a visual scan of the 
list of packages to be installed does not reveal any syslinux files, and 
the GUI does not seem to show dependencies and/or additional files that 
must be installed.  Do I manually use yum to remove the offending 
syslinux file and then rerun the update or will this cripple the system 
making the update impossible?

System information:

NAME="Scientific Linux"
VERSION="7.0 (Nitrogen)"
ID="rhel"
ID_LIKE="fedora"
VERSION_ID="7.0"
PRETTY_NAME="Scientific Linux 7.0 (Nitrogen)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:redhat:enterprise_linux:7.0:GA"
HOME_URL="http://www.scientificlinux.org//"
BUG_REPORT_URL="[log in to unmask]"

REDHAT_BUGZILLA_PRODUCT="Scientific Linux 7"
REDHAT_BUGZILLA_PRODUCT_VERSION=7.0
REDHAT_SUPPORT_PRODUCT="Scientific Linux"
REDHAT_SUPPORT_PRODUCT_VERSION=7.0

from: /etc/os-release

  uname -a
Linux [redacted] 3.10.0-123.el7.x86_64 #1 SMP Thu Sep 11 15:55:14 CDT 
2014 x86_64 x86_64 x86_64 GNU/Linux

extlinux -v
extlinux 4.05  Copyright 1994-2011 H. Peter Anvin et al

syslinux -v
syslinux 4.05  Copyright 1994-2011 H. Peter Anvin et al

What other information do I need?

Yasha Karant