do a DME reset to adjust to the elevation change, you could have damaged the spark plug by not having it in there properly with oil and exhaust blowby. i would replace all the plugs. the intake leaks could have caused some damage to the engine with silicon particulates, get some molybdenum disulfide oil additive to alleviate it.
Alusil, Dinan DME | ITG Air Filter | Eibach/Bilstein HD | 26/20 Swaybars | Iridium plugs | Depo/ProLumen HID | Optima batt. | no AC | Stoptech brake lines, Frozen rotors, brass bushings, Superblue