I know it's easy to swap the spider gears, been working on cars for a long time. Problem is I'm in Rustachussetts. The pull your own parts yards around here barely have anything older than 10 years on the lot. Especially since scrap metal prices went up, alot of yards got rid of their old inventory. And when they take in stuff older than 10 years, straight to the crusher. Running down to the local junkyards is an option I don't usually have.