I was able to get the lifter out of the bore hole with a slide hammer. I have a couple of questions:

1) how much tolerance is there with the bore for the hydraulic lifters? can i just take a little sand paper and smooth out he scratches?

2) Do I need to replace my engine or can I pull the pan and oil pump and run a few cycles of oil through and call it good?

 

I bought a motor with a tap....lifter let go like yours. There is metal trash throughout the motor. Time to tear down and rebuild.

 

The lifter diameter is .842", and the clearance I think, is something like.0015". It is a close fit. I have never had to deal with repairing a damaged bore, but it's a crucial fit.

 

If it's only scratched, a light touch up w/ a dingleberry hone should be GTG.
As for the rest of the engine, refer to post # 2.

 

I texted my local LS builder and he said to replace the cam and lifters and call it good.

I heard the tap and drove for like 5 miles maybe until I pulled over and towed it home. The car was running fine.

Has as anyone has experience running the motor without a full rebuild on a lifter problem like this?

 

This happened to me last year. The lifter flattened and I had to hammer it out from the top since it was stuck. I removed the lifter from the crankcase with an extension magnet. Therefter, I passed a magnet through the lifter oil galleries and caught some shavings. I got a magnetic drain plug and changed the oil after 100 miles. I changed it three more times during the next 2000 miles.

Its OK. The main thing is to check the camshaft bearings when you install the new cam and lifters. If the bearings aren't scored you're good. Good luck with repair.