No need my Brother.
Done so in copious detail couple times in the past (as have others) should the OP choose to use the Search Function graciously supplied by the Forum Owner (but like the Maytag Repairman-rarely used).
However, for you my Friend, once more into the Breach
"Rake Kit" (by all it's Brand Labels) or modified set of Triple Trees (as pertains to the GL) is absolutely and inarguably necessary for a Bike converted to a Trike. It is NOT simply to make the steering easier. That is a nice side effect of the Primary Purpose which is to correct the overall Geometry and Operational Dynamic of the modified Unit.
There is NO Blanket or Cookie-Cutter answer as to degree of increase.
Tube Extensions ARE necessary to return the Backbone of the modified Unit to proper level.
OEM Springs ARE inadequate post-conversion (to each his own on the "proper" mod to correct)
Tapered Head Bearings ARE needed and required.
Fork Braces (Superbrace et al) ARE desirable, a marked improvement, and serve a valid function.
Modifying the Risers (again, to each his own on which) to correct and individualize the Ergonomics of hand positioning for Control & Comfort aren't a "requirement" but damned close.
For the Paul Harvey rest of the Story,,,, Upper Right Corner Area of the Header on every Page:
"Advanced Search"