1993 Silverado 5.3 swap

[LS6_Silverado]

I did i just read this

The cups should have three holes to bolt them to the adapter plates. The bottom one will use a metric bolt, the two top ones you will have to check to make sure if they are metric or SAE. One thing I do to help the cups sit best on the adapters is to either to flatten or remove the raised section that mates to the adapter plates.

I was just wondering what are the adapter plates?

[LS1GMCTruck]

Yes, you also need the adapter plates that are flat plates that bolt to the block. You can make them yourself from dimensions provided here on this site, buy them from places like Street & Performance, or buy them on E-Bay, etc... The cups bolt to the adapter plates. The frame mounts bolt to the cups. I did mine completely differently than most people. I retained my original 4.3 V-6 frame mounts & fabricated a flat steel plate that bolted to the engine, that came forward just far enough to allow me to weld on two tabs that reached down to meet the frame mount. Each of these tabs had a hole near the bottom, so a bolt could slide through them and the frame mount. Simple. This allowed me to put the engine/transmission as low as possible, and as far back as possible. The front of my engine is barely past my frame crossmember. Great center of gravity this way, just what I was after.