I have an all original 1949 Chevy Suburban, 216 engine, three on the tree. For never having been rebuilt it shifted pretty well a month ago. Truck sat for a month outside (Bakersfield, California so not freezing) and now it is hard to shift. Hard to get into first or reverse, can't move the shifter up or down at all to shift into 2nd or 3rd. Any ideas what to check on first? Was hoping to keep driving the Suburban as is until next year when it gets torn apart, so I don't want to rebuild anything.