Ford has discontinued the stock bushings for the IRS Sub-Frame.
Also, from a performance perspective, the stock bushings allow too much movement of the sub-frame, which can lead to wheel hop and/or poor 60' times in high powered cars.
I am developing performance bushings made from UHMW with hardcoated aluminum spacers.
I expect the full kit of 8 bushings and 4 spacers to sell for $400 shipped (lower 48) at this point.
I plan to begin shipments of the completed kits by mid-April.
However, I am offering a $50 discount to early adopters who prepay in full prior to April 1st.
See THIS post on SCCoA for more info.
Please PM me for payment details if you are interested.