Turned the key to leave Lowes this evening and things were bad. Limped it to a better area to check things out, pulled the valve cover and sure enough this time it is intake #1. This head has been reworked twice now (only guides were changed the first time), the second time was just about this time 3 years/40,000 miles ago with new seats, guides, valves ect as that time I lost exhaust #3. No indications of overheating.

Shoddy work, just my luck or just its time ? Other than hardware salvage I am thinking this cylinder head has had its run and will become a test subject for porting practice. 355,000 miles at the time of failure.

My plan forward is to use the cylinder head from the CSX's engine so I took that off this evening. It already had a roller camshaft installed, no idea what of course so I am wondering if I should swap them from the original head ? or just change the sprocket to round tooth and roll on with it ?

A basic garage level refresh is all I am seeing here. There are no machine shops in the area I trust anymore to not screw up and take forever.