With changing the pulley, I have heard of the ones were it makes it easier to change the pulleys in the future? just a couple of bolts, do you have these or are they worth it?

We do, in fact, all of the upgraded pulleys that we sell run a modular hub allowing for quick and easy change between pulleys (under 5 min). For more information about this system, please check out the fitting instructions in the link below:

http://www.maceengineering.com.au/WebRoot/ecshared01/Shops/mace/4E1D/A79D/D800/6FA9/364C/C0A8/D240/1463/PULLEY_INSTALL_instructions_pdf.pdf