30 yrs. ago,  those  rubber isolaters were  26 bucks each.   takes  8 of them.        Not sure if they are even available today..  

I  cut  sidewalls ouf of a  tractor rear,  and   sharpened a short piece of  well stem pipe-  (3 inch)  and  used that as a cookie cutter in the shop press.   The  rubber  was  about  5/8ths-3/4 inch thick.

I tried using a  hole saw,  but that was  slow, smokey,  and  extremely hard on the drill...

Took the old  steel sleeve out of the  smashed isolaters to reuse.    

So far,  they've outlasted the originals  by  15 yrs,  and still look  perfect.    

  
Like  Valhalla,    I  simply used a  hi-lift jack  to  do one corner of the cab at a time.  


edit... you'll  probably have to go in and adjust your  clutch linkage,   and shifter rods as you will  gain  about  half inch  cab elevation!!