You can make a Vette pan work, The engine/trans has to be moved up. I put a 5.3 in a lowered 71 C10 back in 02 & used a Vette pan, The oil drain points right at the cross member, It holds 7 quarts of oil....Makes oil changes interesting & expensive.
If I had to do it over I would use this
http://www.summitracing.com/parts/NA...2593/?rtype=10 Comes with a pick-up tube, windage tray, dipstick & tube, & bolts.....New GM stuff for $150!