1990 GMC Safari has something draining the battery, can't locate problem. It is a factory "Glaval" conversion van, and there have never been any problems with ti until recently. there is no added components, such as stereo's or other items, all is factory, but had it parked a number of years only driving occassionally, and I haad the charging system checked out, put new battery in it, even replaced the alternator that did n't need it, still same prob, it drains the battery. happens overnite so pretty significant drain, has anybody had probs like this? Apprecciate any info Thanks, Tinker