4 speed gearbox to 6 spead?

doubt it ...different sized input shaft ,different splines,flywheel will be different ,bellhousing is different ,different clutch ,different mounts ,prop won't fit the output flange ,and will probably need shortening .doubt if the linkage will fit and would need major modification...1 is an iveco ,probably a zf box ,the other please say if im wrong ,is a merc ...way too much hassle /grief and expense ...and the tacho would need redoing due to the ratios being altered

norb
October 2011