Thinking about casting my own polyurethane subframe busings

Hi everyone. My factory subframe bushings are shot, and I've done aluminum subframe bushings in the past on a '92 SHO and didn't care at all for the vibration. I'm trying to decide on 60A or 80A urethane for my roll restrictor and front mount, and thinking I might just order enough urethane to cast my own subframe bushings.

I've never cast anything before and was wondering if I were to purchase some aluminum SFB's for this car, grease them up and make a mold using some durable expanding foam... if I might be able to get away with filling that foam mold with perhaps 60A or 80A poly? I supposed I would likely need to find some way to seal the inside of the foam mold since the foam is porous, but is this idea feasible at all? Or do I need to find a better material to use to cast the mold?

You might still be able to get both pairs of subframe bushings from a Ford dealership. I acquired a full set about 2 - 3 years ago. I don't remember which pair but the dealer network had well over 100 of them in stock (rear?). The other pair was down to about 20 left back then.

Thanks! Yeah I've seen them on Ebay here and there, but definitely looks like they are depleting. Poly would obviously give it a little more firmness along with vibration, but if the vibration of poly is much less than aluminum I think I might not bother with rubber again there.

How can you tell the subfram bushings are shot? Does it make noise?

Ok my whole subframe shifts and makes noises.

Some moron left one of the four subframe bolts loose the nut broke loose and they left it for me to figure out . After spending around 700 on new suspension componets . It was a loose subframe.....