Solution to 2: Some Assembly Required

These are clues for Three Letter Acronyms. The last letter of every acronym (initialism) matches the first letter of exactly one other, with the exception of the first and last. Forming this chain and reading the middle letters spells out ANY THREE WORDS.

Dominant feature of Complex 39
VAB: Vehicle Assembly Building
Place to watch for TSX updates
BNN: Business News Network
Science guy drops the ball
NYE: New Year's Eve

Charges $27 to send your scores
ETS: Educational Testing Service
Movement from quadratic potential
SHM: Simple Harmonic Motion
Don't wear earrings in one of these
MRI: Magnetic Resonance Imaging
Ad-hoc firestick
IED: Improvised Explosive Device
Deal breaker put in place by Nixon
DEA: Drug Enforcement Administration

Biggest has four zeroes
AWG: American Wire Gauge
The red elephant
GOP: Grand Old Party
Large mass established 1949
PRC: People's Republic of China
Will be -5 this summer
CDT: Central Daylight Time
King and Simcoe is their home turf
TSO: Toronto Symphony Orchestra

In retrospect, these clues should have been easier: They were designed as crossword clues, but seeing that a chain can be constructed demands that you solve nearly every clue correctly.

ANY THREE WORDS