ive seen some guys just line it up at bolt in in and others have lined them up then put , I believe, 0.015 shims between gears and then tighten the bolts, says it prolongs life of pump?...how to prime LS without expensive pump...ive seen a few homemade ideas....some guys say to just start it..i didn't prime the first time but the pressure shot up too 60 or 70psi on first start up within a few seconds...