What if he was going from a nonTRD and wanted bilsteins??? This way you get the performance from the shock and the full 3" of lift from the spacer. Its nothing like buying Muds and cutting the lugs off.
OK, simile eludes you - and you missed the point entirely.
He clearly stated he wants LIFT, and purchased the 5100s. It doesn't matter what his previous suspension configuration was, TRD or not. Why would you suggest that he throw away the benefit he PAID for?
Coil spacers are a lower-performing lift model than a shock body allowed its full travel capabilities. They allow the suspension components to droop beyond the help of the shock's ability to reduce it. It therefore puts his ball joints at risk due to impact from excessive downtravel because they become the limiting component. That's just a physical fact.
He will
not "...get the performance from the shock..." with the coil spacers, especially 3" spacers, as you suggest, and the OP should be clearly aware of that. I have the DayStar 2.5" front coilover spacer lift on my Tundra; I know what I'm talking about.
To the OP: I strongly urge you to do more research here on lifts, especially
this writeup done by
DevinSixtySeven. :tu: