BBC Poly Motor Mount Inserts

[LOW 7FO]

Hi All,

Let me first say I've searched for a few hours and called the manufactures and am still left wondering how to go about this. I have '75 SWB Big 10 2WD. It has a factory 454 and I want to replace the rubber motor mount with the poly inserts sold by Energy Suspension or Prothane.

This is where my problem starts...neither one of these places make the poly insert for BBC 73-84. They do make them for SBC 73-87, so will the SBC insert fit my my BBC mounts? Or do I need to buy the SBC mount and use the SBC poly inserts? The SBC and BBC mounts are visually different as seen online parts stores for SBC/BBC with different part numbers. Energy Suspension sells 3.1121G inserts that fit 85-88 BBC...is that the one I need for my 75? I don't think the mount style changed in those years? Lastly, Brothers Trucks claims to sell 73-87 BBC inserts and they told me they are made by Prothane. Prothane told me they don't make them for BBC application.

I'm lost and need help I don't want to start buying all these things and experimenting if I don't have to.