Welcome to this site, Well first of all when i bought my car i took a compression tester the owner thought i was weird but hey im a car guy and i wanna know what im getting, after all im paying for it. Well a compression tester will tell you how healthy the engine actually is. Do a visual inspection, Checking if there's any leaks especially the rear main seal. These 5.0 have a tendency to leak at high miles. Check the oil, look for any signs of water in there. when you drive it check for any vibrations unusual noises, i personally have the auto so im sure some one with the t-5 they can help you with that and what to look for.