engine head install... a few questions

[tjn]

I purchased a remanufactured head for my 1990 535i that was leaking coolant and always boiling over. Sure enough, after taking off the head, the gasket was failing at cylinder number 6. The engine top came from headsonly.com in Texas (was this a bad idea or does anyone have any experience with them?).
Basically, I am checking to see if anyone has any pointers or tips on the installation. My questions are:
There are a few threads (the threaded shaft without the nut) missing in the manufactured head that are needed to bolt the intake manifold and exhaust on... How do I get these, or can I take them somewhow off my old head? I tired to twist them off the old head, but they seem permanently embedded onto it!
The new engine head stamp says its a 1988... is that a problem?
Should I install new injectors or doing any other work while I'm at this point, ie: Should I replace the timing chain or anything else besides (the engine is at 300,000 miles)
Thanks for any tips and help!!
tim

[grave77]

I'm not sure I would answer all your questions, but I can tell few things you should do. first replace all the screws you have with Trox type instead of Hex screws as the Trox version resists heat and prevent your engine from what they have called it the timed bomb !! next thing is as your engine made 300,000 so it's time for few other possible change, you're not going to open up your engines head every day so get new vavles and seels also replace the oil bolts on the spray bar. check your camshaft since replacing it needs to get the head off so it's better you do it now.

about the injectors I think changing them won't be a problem. but 300,000 is quit a usage !! if a newer ( second hand ) engine is cheaper then I prefare you do so and save your self the headache. check Bruno's site http://www.bmwe34.net/E34main/Maintenance/Engine/headgasket_M30.htm

you will find extra info there. hope this would help.