You don't want to drill that hole all the way through because you want the smaller lower portion of the hole as a guide for the Tee handle.
Do not tighten the rear tang Tee handle as it is used to keep the epoxy from running out.
The inletting pins are useful for aligning the barreled action with the machined stock and the Tee handles during the later stages of inletting as they allow you to pull the bottom metal and top metal together quickly and easily.
Insert the Tee handles in the forward and rear tangs and fit them into the screw holes in the machined stock to correctly align the parts.
Once the barreled receiver is approximately half inletted into place I use the Tee handles to more perfectly align and slowly draw the bottom metal and top metal together.
This time I use both Tee handles to tighten the top metal and bottom metal in place using first one than the other.
FDB's Rocfast service covers all products encompassed in their profile - this includes: budget locks, camlocks, compression locks, knob locks, rod locks, spanner locks, waterproof locks, toggle latches, concealed hinges, flush hinges, butt hinges, lift-off hinges, 'piano' hinges, stainless hinges, weld-on hinges, earth bars/busbars, flush handles, grab handles, lever handles, tee handles
, paddle handles, padlocks, support stays and seals/gaskets.