What else can i delete except Apollo in this new build to make it upto 180 mb
Why don't you want to remove Apollo from ROM? You can copy it to your SDcard and install it after flashing the ROM.
From ROM I removed:
bootanimation and some sounds
CMFileManager (replaced by Filemanager from Android 2.3 = 113KB)
and trimmed LatinIME to 3MB (some of these I installed later, but then, they'll go to /data)
From GApps I removed:
Now /system is occupied 156MB/160MB