First post, I was directed to the forum by a google search but could not continue my research due to not having permission, so here it goes!

I've got a 3 year old pool with a sta-rite cartridge filter, and the filters are now past cleaning and need to be replaced. I caught a glimpse of a post that suggested I could buy new "innards" to convert the from cartridge to DE, but have a few questions: Are all of the system 3 casings exactly the same? What is the cost of doing this (less than $450 cartridge purchase)? I am reasonably, but not exceptionally, handy, is this a project that I could handle myself? This is my first salt pool, can I even use a DE filter with a salt pool?

Thank you in advance for any help that you can offer, I need to get moving with something fairly quickly to get the pool flowing nicely again.