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Almost ready to mount the intake and exhaust manifolds back on the flathead six of the 46 Plymouth. When I pulled the manifolds, some of the shorter studs came out of the block, while others stayed in place as the nut was removed....my (2) long studs that go through the exhaust manifold center were a bit more of a problem, as both snapped on me - however I was able to get the studs out at that point with only minimal thread damage to the outside two threads on one of the two studs... After cleaning up the old somewhat rusty threads with a wire type bottle brush, they look nice and clean now. I am now able to thread the studs into the side of the block - by hand - until they seat against the hole...and my two longer studs are probably the easiest to thread in by hand, but really basically they all feel relatively close to the same, in tightness - not a lot of difference. Thinking along the lines of getting a good seal into the water jacket area, and also to try and prevent them from loosening up ..with these engines basically running a non pressurized coolant system - I can see where leakage is not as big a fight as it would be on a modern engine...and again I may be wrong in my thinking (as this is my first time around a flathead motor ),..but I'm thinking that getting the studs anchored well is gonna be more the issue than difficulties associated with coolant leakage - course that said - nothing will ruin your day faster than a coolant leak.. I have found the following.... 1: Actually Plymouthy Adams found this stuff for me on ebay, a month or so ago.....it's a high temp, (690 degrees) slightly thicker than normal, Teflon type tape,...that should seal really well against leaks, but offers no thread-locking capabilities.... 2: Loctite has a product called Loctite 2422, the tech told me it's good in regards to contact with antifreeze, it has the highest heat rating of any of the Loctite products, (650 degrees)...and it's the medium rated blue colored Loctite that can still be dis-assembled with hand tools. Would appreciate any feedback from the forum members regarding the above... I don't know how hot the threaded area of the block at the manifold studs gets,...with the coolant from the water jacket being right there touching the end of the studs (that should help greatly), but still this has got to be close to the hottest place on this engine block,....which is a normal/stock 217 flathead 6 cylinder. Anyone out there with any experience regarding how hot these manifold studs might get ? Not trying to make this harder than it has to be - although I can be pretty good at doing just that very thing from time to time I would just snug them up on occasion, as I've read some folks state they do - but 99% that's gonna just retighten the nut as the stud continues to loosens. Bolts rather than studs would eliminate some of this, as you would be turning the entire bolt when you re-tightened in the future, however I'm hoping to use the tight fit studs I had a machinest make..as a normal 3/8-16 class-2 thread is pretty loose on the first 3 rows of threads on one of my long studs. Trying to exercise the old "ounce of prevention is worth a pound of cure" thang here... Any and all reply's are welcome, thank you all in advance. Steve