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Prime the oil pump before attempting a start-up to ensure the bearings are lubed. Also put a tablespoon of ATF fluid into each cylinder to oil the rings and help them for the first few revs. Don't use too much - just a tiny bit is enough - and leave it to soak in for a day or so.
See here:
http://www.opelgt.com/forums/6a-engi...rs-blocks.html
for some idea of the dry start-up pre-oiling procedure.