Would any overheating issues arise from placing the WLD3343 and WTC3243 in a closed area ~ 7″x5″x3″? If so, would the associated thermal solution kits help to relieve this problem?
If the maximum internal temperature in the box is kept at or below 85°C and you use the heatsink and fan (if required-see SOA charts for the WLD3343 and WTC3243) you will not have a problem.
In general, the units can operate up to 0.5 A with no heatsink or fan; if you add the heatsink you can operate up to 1 A; if you add a heatsink and fan you can operate to 2 A for both units. Follow the links to the SOA charts above and do the calculation to be certain of your heatsink and/or fan needs.