Reassembling by guessing and trial. 1973 Javelin

I have been very slowly gaining on rounding up hardware to install engine components on the 401 which is to be installed in my 73 Javelin. I have found 9, 3/8-16 2 inch long bolts which are drilled 1/8 inch dia. and 3/8 inch deep on the threaded end. Are these bolts part of the engine/automatic transmission assembly to the car? Thank you again.

You do know it's unlikely anyone's going to take their engine/transmission apart to help you assemble yours don't you?
And it's also not to likely they will remember the length of each bolt in the assembly.

What you've got to do is measure the depth of each threaded hole, the add the depth of whatever is being bolted to that, and see what bolt you have that will fit that requirement.

You can usually tell if there were washers or not by the witness marks left by the old washers on the bolt opening.

Usually the transmission-engine assembly is held together by the same size bolt, same head hex size, but different lengths.
You're dealing with a 40+ year old car, the bolts you have may or may not be the originals.
I've got several buckets of bolts out in my shop from disassembling AMCs engines from their transmissions, but their not necessarily the same as what you have.

thanks for backing me up on that one Walt, I have a set of these bolts from a 76 401 with free flow manifolds. I understood the concept a little but after your explanation, I understand it much better.