[Nexus 5 Original Android Development] danarama:
Thanks for your insight. I am still having issues.

envsetup.sh

# The gcc toolchain does not exists for windows/cygwin. In this case, do not reference it.
export ANDROID_EABI_TOOLCHAIN=
local ARCH=$(get_build_var TARGET_ARCH)
case $ARCH in
x86) toolchaindir=x86/i686-linux-android-$targetgccversion/bin
;;
[B] arm) toolchaindir=arm/linaro-$targetgccversion/bin[/B]
;;
mips) toolchaindir=mips/mipsel-linux-android-$targetgccversion/bin
;;
*)
echo "Can't find toolchain for unknown architecture: $ARCH"
toolchaindir=xxxxxxxxx
;;
esac
if [ -d "$gccprebuiltdir/$toolchaindir" ]; then
export ANDROID_EABI_TOOLCHAIN=$gccprebuiltdir/$toolchaindir
fi

unset ARM_EABI_TOOLCHAIN ARM_EABI_TOOLCHAIN_PATH
case $ARCH in
arm)
[B] toolchaindir=arm/linaro-$targetgccversion/bin[/B]
if [ -d "$gccprebuiltdir/$toolchaindir" ]; then
export ARM_EABI_TOOLCHAIN="$gccprebuiltdir/$toolchaindir"
ARM_EABI_TOOLCHAIN_PATH=":$gccprebuiltdir/$toolchaindir"
fi

TARGET_linux-arm.mk

# You can set TARGET_TOOLS_PREFIX to get gcc from somewhere else
ifeq ($(strip $(TARGET_TOOLS_PREFIX)),)
TARGET_TOOLCHAIN_ROOT := prebuilts/gcc/$(HOST_PREBUILT_TAG)/arm/linaro-$(TARGET_GCC_VERSION)
TARGET_TOOLS_PREFIX := $(TARGET_TOOLCHAIN_ROOT)/bin/linaro-
endif

Error

Import includes file: /home/dan/android/SlimKat/out/host/linux-x86/obj/STATIC_LIBRARIES/libmincrypt_intermediates/import_includes
Export includes file: system/core/mkbootimg/Android.mk -- /home/dan/android/SlimKat/out/host/linux-x86/obj/EXECUTABLES/mkbootimg_intermediates/export_includes
Export includes file: build/libs/host/Android.mk -- /home/dan/android/SlimKat/out/host/linux-x86/obj/STATIC_LIBRARIES/libhost_intermediates/export_includes
Import includes file: /home/dan/android/SlimKat/out/host/linux-x86/obj/STATIC_LIBRARIES/libhost_intermediates/import_includes
Export includes file: build/tools/acp/Android.mk -- /home/dan/android/SlimKat/out/host/linux-x86/obj/EXECUTABLES/acp_intermediates/export_includes
mkdir -p /home/dan/android/SlimKat/out/target/product/hammerhead/obj/KERNEL_OBJ
Notice file: system/core/libmincrypt/NOTICE -- /home/dan/android/SlimKat/out/host/linux-x86/obj/NOTICE_FILES/src//lib/libmincrypt.a.txt
mkdir -p /home/dan/android/SlimKat/out/target/product/hammerhead/system/lib/modules
Import includes file: /home/dan/android/SlimKat/out/host/linux-x86/obj/EXECUTABLES/mkbootfs_intermediates/import_includes
Export includes file: system/core/cpio/Android.mk -- /home/dan/android/SlimKat/out/host/linux-x86/obj/EXECUTABLES/mkbootfs_intermediates/export_includes
/bin/bash: prebuilts/gcc/linux-x86/arm/linaro-4.8/bin/linaro-gcc: No such file or directory
make: *** [/home/dan/android/SlimKat/out/target/product/hammerhead/obj/lib/crtbegin_static1.o] Error 127
make: *** Waiting for unfinished jobs....
Export includes file: bionic/libc/Android.mk -- /home/dan/android/SlimKat/out/target/product/hammerhead/obj/SHARED_LIBRARIES/libc_intermediates/export_includes
[B]/bin/bash: prebuilts/gcc/linux-x86/arm/linaro-4.8/bin/linaro-gcc: No such file or directory[/B]
make: *** [/home/dan/android/SlimKat/out/target/product/hammerhead/obj/lib/crtbrand.s] Error 127
dan@dan-Latitude-E6410:~/android/SlimKat$

Edit, Hang on - I may know what I did wrong there