Made some tweaks similar to @pheiduck's suggestions.

Arch-Linux/LCD35-show

@@ -3,6 +3,9 @@
 # Change working directory up to the main directory to allow easier access to the boot, etc, and usr directories.
 cd ..
 
+# Install wget...
+sudo pacman -Sy --needed --noconfirm wget
+
 sudo ./system_backup.sh
 
 if [ -f /etc/X11/xorg.conf.d/40-libinput.conf ]; then
@@ -46,7 +49,7 @@ echo "gpio:resistance:35:90:480:320" > ./.have_installed
 #FBCP install
 wget --spider -q -o /dev/null --tries=1 -T 10 https://cmake.org/
 if [ $? -eq 0 ]; then
-    sudo pacman -Sy --needed --noconfirm cmake 2> error_output.txt
+    sudo pacman -Sy --needed --noconfirm cmake make 2> error_output.txt
     result=`cat ./error_output.txt`
     echo -e "\033[31m$result\033[0m"
     grep -q "^E:" ./error_output.txt
@@ -66,14 +69,14 @@ if [ $? -eq 0 ]; then
         fi
         sudo mkdir ./rpi-fbcp/build
         cd ./rpi-fbcp/build/
-        sudo cmake ..
+        cmake ..
-        sudo make
+        make
         sudo install fbcp /usr/local/bin/fbcp
         cd - > /dev/null
         type fbcp > /dev/null 2>&1
         if [ $? -eq 0 ]; then
             sudo cp -rf ./Arch-Linux/usr/99-fbdev-fbcp.conf  /usr/share/X11/xorg.conf.d/99-fbdev.conf
-            sudo cp -rf ./etc/rc.local /etc/rc.local
+            #sudo cp -rf ./etc/rc.local /etc/rc.local
         fi
     else
         echo "install cmake error!!!!"

Arch-Linux/rotate.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 cur_dir=`pwd`
-if [ ! -f $cur_dir/.have_installed ]; then
+if [ ! -f $cur_dir/../.have_installed ]; then
 echo "Please install the LCD driver first"
 echo "Usage: sudo ./xxx-show. xxx: MHS35,LCD35,MPI3508 etc."
 exit
@@ -39,13 +39,13 @@ exit
 fi
 
 #get screen parameter
-tmp=`cat $cur_dir/.have_installed`
+tmp=`cat $cur_dir/../.have_installed`
-output_type=`cat $cur_dir/.have_installed | awk -F ':' '{printf $1}'`
+output_type=`cat $cur_dir/../.have_installed | awk -F ':' '{printf $1}'`
-touch_type=`cat $cur_dir/.have_installed | awk -F ':' '{printf $2}'`
+touch_type=`cat $cur_dir/../.have_installed | awk -F ':' '{printf $2}'`
-device_id=`cat $cur_dir/.have_installed | awk -F ':' '{printf $3}'`
+device_id=`cat $cur_dir/../.have_installed | awk -F ':' '{printf $3}'`
-default_value=`cat $cur_dir/.have_installed | awk -F ':' '{printf $4}'`
+default_value=`cat $cur_dir/../.have_installed | awk -F ':' '{printf $4}'`
-width=`cat $cur_dir/.have_installed | awk -F ':' '{printf $5}'`
+width=`cat $cur_dir/../.have_installed | awk -F ':' '{printf $5}'`
-height=`cat $cur_dir/.have_installed | awk -F ':' '{printf $6}'`
+height=`cat $cur_dir/../.have_installed | awk -F ':' '{printf $6}'`
 
 if [ $output_type = "hdmi" ]; then
 result=`grep -rn "^display_rotate=" /boot/config.txt | tail -n 1`

Arch-Linux/usr/99-calibration.conf-35-0

@@ -0,0 +1,6 @@
+Section "InputClass"
+        Identifier      "calibration"
+        MatchProduct    "ADS7846 Touchscreen"
+        Option  "Calibration"   "268 3880 227 3936"
+        Option  "SwapAxes"      "0"
+EndSection

Arch-Linux/usr/99-calibration.conf-35-180

@@ -0,0 +1,6 @@
+Section "InputClass"
+        Identifier      "calibration"
+        MatchProduct    "ADS7846 Touchscreen"
+        Option  "Calibration"   "3880 268 3936 227"
+        Option  "SwapAxes"      "0"
+EndSection

Arch-Linux/usr/99-calibration.conf-35-270

@@ -0,0 +1,6 @@
+Section "InputClass"
+        Identifier      "calibration"
+        MatchProduct    "ADS7846 Touchscreen"
+        Option  "Calibration"   "227 3936 3880 268"
+        Option  "SwapAxes"      "1"
+EndSection

Arch-Linux/usr/99-calibration.conf-35-90

@@ -0,0 +1,6 @@
+Section "InputClass"
+        Identifier      "calibration"
+        MatchProduct    "ADS7846 Touchscreen"
+        Option  "Calibration"   "3936 227 268 3880"
+        Option  "SwapAxes"      "1"
+EndSection

system_backup.sh

@@ -50,11 +50,15 @@ if [ -f /usr/share/X11/xorg.conf.d/99-fbturbo.conf ]; then
 sudo cp -rf /usr/share/X11/xorg.conf.d/99-fbturbo.conf ./.system_backup/
 fi
 #sudo cp -rf ./usr/99-fbturbo.conf-original /usr/share/X11/xorg.conf.d/99-fbturbo.conf
+if [ -f /etc/rc.local ]; then
 sudo cp -rf /etc/rc.local ./.system_backup/
 #sudo cp -rf ./etc/rc.local-original /etc/rc.local
+fi
 
+if [ -f /etc/modules ]; then
 sudo cp -rf /etc/modules ./.system_backup/
 #sudo cp -rf ./etc/modules-original /etc/modules
+fi
 
 if [ -f /etc/modprobe.d/fbtft.conf ]; then
 sudo cp -rf /etc/modprobe.d/fbtft.conf ./.system_backup

system_restore.sh

@@ -39,8 +39,14 @@ sudo cp -rf ./.system_backup/99-fbturbo.conf /usr/share/X11/xorg.conf.d
 fi
 sudo cp -rf ./.system_backup/cmdline.txt /boot/
 sudo cp -rf ./.system_backup/config.txt /boot/
+
+if [ -f ./.system_backup/rc.local ]; then
 sudo cp -rf ./.system_backup/rc.local /etc/
+fi
+
+if [ -f ./.system_backup/modules ]; then
 sudo cp -rf ./.system_backup/modules /etc/
+fi
 
 if [ -f /etc/inittab ]; then
 sudo rm -rf /etc/inittab