ITEM NAME:fit for GM TH350 TH400 LS2 LS3 LS6 6.0 LS7 700R4 Adapter Spacer LS1 Flexplate hf LS1 Based Engines Flexplate Adapter Spacer Fit For TH350 TH400 Conversion Swap LS2 LS3 LS6 5.3 6.0 LS7 SPECIFICATIONS.LS1 Based Engines Flexplate Adapter Spacer Fit For TH350 TH400 Conversion Swap LS2 LS3 LS6 5.3 6.0 LS7. Compatible With: Fit for use on 1998-2004 LS1 based engines using a TH350 or TH400 transmission.