[VWNate1]

Whoops ! you're correct, tube headers often (not always) work better with fasteners on the ends .

It's still critical to tighten the whole mess from the center outwards, not any other way .

When the GM HEI was new they spec'd .065" on the spark plugs, we thought it was crazy but they started and ran so easily in the sub zero temps Down East....


The changed that after a few years but running .045" minimum is wise .

The only downside I've ever experienced is accelerated wear on the caps, rotors and wires......

The plugs proper wear a bit faster but no biggie .

I hope everyone here knows to never use platinum tipped spark plugs in older engines ! .

They run colder and cause fouling problems quite often .

I think that 1968 292 looks great ~ those who work and drive these old rigs daily (more common than most realize) know how sturdy they are and if you keep up on the routine HOT OIL & FILTER CHANGES the thinwall bores don't wear out much .

All through the 1960's and 1970's there were millions of GM products with thinwall (1963>) i6 engines that blew smoke and drank oil, this was caused by owner failure to properly maintain them .

The previous generations of GM i6 engines could be overhauled with massive (up to .016") taper in the cylinder yet run fine and not smoke .

@Dwyert : who knows ? maybe one day he'll tire of it and sell to you for an affordable price .