Agree with other posters on doing a couple solid burns on one.  If you aren't totally set on the kit - Watch yard sales and scrap piles for the 22" Weber as mentioned - they have half the parts you need including a great lid.  People throw them out because they dont clean em and the bottom rusts out of them.  I made grates / burn basket with scrap grill parts, replacement weber grills from Home Depot and some adjustable shelf hardware.  You dont need to overthink the vents on the bottom 3x 3/4" iron pipe nipples with caps on them work fine.  Caps hanging on their loose or just threaded in lets enough air in I find.