Just wondering if I can use a standard 1 inch to 1 1/8 inch shim with a Thomson stem or do you need to buy the Thomson shim? Also is a different end cap required? This if for using a Thomson on a Soma 1" fork with a IRD Technoglide Headset if that matters. Have a shim in the parts box but Thomsons have a little different clamping mechanism with that internal piece.

All 1 - 1 1/8 shims are pretty much the same. Use a top cap that matches your stem.